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Dual Plug Heads

Started by JW113, April 17, 2020, 11:34:30 AM

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JW113

Nibroc, here's your update.
:SM:

I picked up the heads on Monday, and painted them. (had the shop bead blast the old paint) So today I'll be working to get the top end back together, I think I have all the parts now. I spent a lot of time tracking down gaskets that were the rubber coated steel type. No one supplier had them all, in fact the base gaskets came from Italy!

The heads look pretty good. The plugs are more or less located opposite from one another in the chamber. The plug angles are different, but at the end of the day I don't think that makes much difference. I do think I'll take a dremel and dress the ends of the new plug holes, I don't like seeing the threads exposed like that. Possible "hot spot".

He was not able to put valve seals on, there is simply not enough room. He did use Kibblewhite manganese bronze guides, and ran minimal clearance, so oil draw though them should be minimized. Also used Evo/TC style Kibblewhite valves and Kibblewhite springs.

[attach=0,msg1342847]

[attach=1,msg1342847]

[attach=2,msg1342847]

[attach=3,msg1342847]

The cylinders were bored to .040" over, and using Wiseco 10:1 forged pistons. Also installed a set of Andrews R5 cams. Will be interesting to see how this thing runs now. Hopefully a little less blue smoke!

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

nibroc

should be a lot less blue smoke

cheech


jls 64

js

sharkoilfield

Wow; those look nice.  Is there a pretty pronounced dome on the Wiseco's?  It'll be interesting to hear your riding impressions...

Racepres

Quote from: sharkoilfield on April 18, 2020, 06:47:43 AM
Wow; those look nice.  Is there a pretty pronounced dome on the Wiseco's?  It'll be interesting to hear your riding impressions...

I can tell you that with the "Pronounced Dome" on my IH dragbike...we needed to put Dimples in the Piston Dome to clear the plugs!!!!
[attach=0]

JW113

Yes the domes are up there, but so is the stock piston. The the Wiseco's, it appears the area is filled in a bit more.

One interesting thing with dual plug, by shining a light into one hole, you can get a pretty clear view of what's going on in there from the other hole. With the plugs I'm using, the only part that extends into the chamber is the electrode. I'll check it out if they interfere with the piston crown.

I'm thinking my machine shop guy used a bit too much valve spring, esp on the exhaust. Turning it over in 4th with the rear tire takes a bit of arm now.

After I got the heads and rocker boxes on, the problem now is what to do with the coil. Am using a Dynatek four tower DC6-4, and using the stock ironhead mount, it interferes with the front rocker box. The other bad feature of this coil is no screw terminals like typical HD coils. It has a pigtail hanging out of it to a connector, so no convenient "terminal block" at the coil to connect the other ignition wires to. Wishing I had gone with the Nology mini coils. Oh well, time to put on the creative hat and figure it out.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Racepres

I ended up with 2 MSD super coils... pricey... but no F-Ups...I have a Butt Heavy FXR type Coil mount that will handily hold a pair of twin tower Dyna coils that I will be trying in the very near future..

JW113

OK, think I have it figured out. I have the tank mounted with a hole through the top frame tube. I can just use the same to raise the coil up enough to clear the rocker box. But now to figure out how to connect ring terminals to free hanging pigtails. Maybe just use 10-32 bolts and nuts with some rubber hose to insulate for now.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

cheech

Quote from: JW113 on April 18, 2020, 01:21:11 PM
But now to figure out how to connect ring terminals to free hanging pigtails. Maybe just use 10-32 bolts and nuts with some rubber hose to insulate for now.
-JW
It come with the other side of the connector pigtail as shown in  instructions?
Why not use some male/female bullet terminals then heat shrink? They are available uninsulated also.
[attach=0]

Racepres

That's nice... but I personally do Not trust that coil... granted mine was quite a long time ago... maybe they got Better??
Of course that coil will Not work for My use anyway...as I need a coil with at least 4 ohms primary!!!!
Maybe I should try one again with the MSD Box!!!!!

JW113

There are not a lot of choices for dual output four tower coils. If this one goes tits up I'll go with two Nology coils.

I could of used bullet connectors for the two coil trigger wires, but the problem is the +12V wire. I need 5 connections at that point. The coil wire, the run/kill wire, the ignition wire, the power wire to the Hi-4, and power wire to the AGR. I ended up using screws/nuts through the ring lugs until I think of something better.

Now off to find a parts store that is open and buy a set of plug wires, and it's ready to hit the start button.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

turboprop

I am real curious to see how this turns out. I rarely see iron heads in good shape. Most are pretty ratty, but that is not the case here. Isn't this the bike that you recently put the CV carb on?
'We' like this' - Said by the one man operation.

JW113

Yes. It went from S&S E, to CV-40, to S&S B, now back to CV-40. After curing the off idle cough and getting the jetting close with the AFR, it was running quite nice. And then started smoking. Since I had to pull the top end off, well, you know...
:wink:

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

cheech

Quote from: JW113 on April 19, 2020, 08:32:59 AM

I could of used bullet connectors for the two coil trigger wires, but the problem is the +12V wire. I need 5 connections at that point. The coil wire, the run/kill wire, the ignition wire, the power wire to the Hi-4, and power wire to the AGR. I ended up using screws/nuts through the ring lugs until I think of something better.

-JW
I was just thinking of the trigger wires.  :crook: But if you do have the pigtail as I showed in my snip is it correct showing a separate wire crimped in with the power to got to your HI-4?
If so that's one out of the loop. And FWIW I've "daisychained" in situations like that. Have 2 crimped in one to branch out. Just a thought, throwing some ideas out.
And is "AGR" a typo? Assuming AFR?

cheech

Quote from: turboprop on April 19, 2020, 08:43:01 AM
I am real curious to see how this turns out. I rarely see iron heads in good shape. Most are pretty ratty, but that is not the case here.
No doubt. Original owner 79 I believe was the year, was on the local Craigslist. Appeared in ad showroom new, unmolested. Started out at $6K'ish.
Sat a year or so, was last on there for $2700. Thought man that's a decent deal if anyone wanted one not ratted out.

Racepres

Picture of the smoothest IronHead I ever rode on the street..
Belongs to Eldest...
Not Fastest, quickest, most comfortable... Noooo Smoothest engine and Shifting, and easy clutch even!!

JW113

Correct, AFR. I hit that pesky key next to the F by accident.

Beware the '79 XL. Not saying they are bad bikes, but they have a lot of one year only stuff. Exhaust choices are VERY limited. Rear brake set up is Rube Goldberg.

Not the way I had intended to spend a Sunday morning. I had to hit up 5 auto parts stores until I found one that had a universal spark plug wire set. Finally at O'Rileys they had an Accel set, but even that only came with right angle coil terminals and caps. What ever, will work OK for now.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

JW113

Success! It fired right up, no smoke, no scary noises. I ran it for about 4 minutes at 2K, until the heads started to feel warm. Will let it cool down a little, then do 2 or 3 more heat cycles before taking it around the block. Just for the sake of doing it, I had peeked into the oil tank. It was about 3/4 empty! Pulled the case drain, got a couple quarts out. I figured it might wet sump a bit, it's been sitting for 5 months. Evidently more than 'a bit'. Going to have to look into that I guess. One of the charms of an Ironhead, the oil pump comes off real easy. Save that for an other time, too many other fish to fry first.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

cheech


JW113

April 19, 2020, 05:58:41 PM #20 Last Edit: April 19, 2020, 07:34:34 PM by JW113
Well it has been a fun day. Ironhead all back together and running. And now the agonizing phase of breaking the damn thing in. I went around the block a few times, with the damn thing BEGGING to be flogged like a read headed stepchild. Like all Ironheads do. I resisted. You know how it is, give it some throttle, and once it gets past 3K starts picking up speed on it's own, then you're forced to back off. I'm thinking April is going to be even more difficult to weather through than it already will be given this pandemic stuff. Can't help it, I'm not a patient dude.

:chop:

  :baby:

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

JW113

OK, here it is.

[attach=0]

That big honkin' coil tucked up under the tank:

[attach=1]

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Hossamania

That is a great looking machine! I bet it sounds fantastic. Have fun!
If the government gives you everything you want,
it can take away everything you have.

turboprop

That is a clean ironhead. Very cool.
'We' like this' - Said by the one man operation.

cheech

JW did you get it in that state? Or build into that? Looks nice. :SM: :up:
Coil looks factory from my perspective.
BTW, what little riding you did do, how the tune look on the AFR gauge after all the changes?

JW113

Yes it's a CA bike, I bought from a friend back in 2001. I started several project ideas with it, but never go more than half way only to tear it all apart and stuff it in the shed. I finally figured out what I wanted of it, and thus here it is. I did sort of a build up blog a few years ago while I was putting it together.

https://harleytechtalk.com/htt/index.php/topic,92382.0.html

The AFR was reading on the rich side at steady cruise ~35-40mph, like 12.6:1. I think the last thing I did was pop some shims under needle. I need to take it out a few more times and let it get fully up to temp, then see how it reads. I want to get a few laps on my "break in course" before puttin' the spurs to it. I also pulled about 5 degrees of timing out of it, so still need to get that optimized for the dual plugs.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Racepres

I can't do that Front End on an Ironhead, but... that is strictly Personal... I love an Ironhead... and one day I will Finish my Digger!!!! it also is Not everyone's "cup O tea"

cheech

Quote from: JW113 on April 20, 2020, 08:57:22 AM
Yes it's a CA bike, I bought from a friend back in 2001. I started several project ideas with it, but never go more than half way only to tear it all apart and stuff it in the shed. I finally figured out what I wanted of it, and thus here it is. I did sort of a build up blog a few years ago while I was putting it together.

-JW
By state I meant did you buy it like it is, "that state of build" so to speak.  Sorry for the confusion. Ill check the linked thread out.

JW113

Got it. This is what it looked like when I got it from my pal Surfer Bill. He had bought it from another guy here in San Jose as a complete basket case. He assembled it and got it running, but it was pretty much a cobble job.

-JW

[attach=0]
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Racepres

Quote from: JW113 on April 20, 2020, 10:37:21 AM
Got it. This is what it looked like when I got it from my pal Surfer Bill. He had bought it from another guy here in San Jose as a complete basket case. He assembled it and got it running, but it was pretty much a cobble job.

-JW

[attach=0,msg1343327]
IMHO... the '78 was the Last Great Ironhead... Love the Dual Disks too... the '77 would be great... without that damn Pie slice/cloverleaf front brake....
PS... I really like your "new" exhaust... who made that??? nothing really wrong with the one that was on it... but I Dislike slash cuts and or turnouts.. personally..

JW113

Believe it or not, those are HD "performance" pipes before there was a Screamin Eagle. I believe they were made by Cycle Shack. They are actually for 79-85, didn't realize that when I bought them. I had to modify the bracket for the '78 frame. Not ideal, need to make a better one at some point. I also had them powder coated, not a big fan of chrome in general.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

turboprop

At some point you have got to get this on the dyno (and possibly some scales) for all us that are watching this.

PS - This thread got me interested in iron heads (again). I just did a quick check on Craigslist and Ebay. Nothing on CL and just a few ratty choppers and over priced XRs on eBay. Wasn't that long that owners of almost stock iron heads could not give them away.
'We' like this' - Said by the one man operation.

JW113

Indeed, that is the plan. I had already taken it in to have it dyno tuned with the Super B on it. The guy did a miserable job, is supposedly a savant at tuning FI, but I learned he'd never even touched a B before. I should have demanded my money back, but the shop owner is my machinist and long time friend. Will take it up to RC Cycles after it's broken in. But this time, I'm going to use the AFR and tune it myself beforehand, then let Bob dial it in the rest of the way. If it needs it...

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Racepres

And being Contrary... I don't give nuthin for Dyno runs...
The 1/4 Mile MPH will tell you all you need to Know... leave easy get in High gear and tell me the MPH!!!!

14Frisco

Quote from: JW113 on April 20, 2020, 12:30:39 PMWill take it up to RC Cycles after it's broken in.

I had one of my bikes dyno tuned by Bruce @ Horsepower Express in Campbell several years ago.  He closed shop quite a while ago I believe, do you know if someone "took over" his business?

JW113

Bruce is long gone and no one took over his business. In fact, there is almost nothing left in the south bay area for HD oriented shops and even parts. Even half the HD dealers are gone now. Dudley Perkins HD is no more.

Drag strips are fine if you happen to live near one I guess. For me that would be Sacramento, 120 miles away. Personally, I find the plots of torque curve and AFR very informative. And not at just WFO.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

turboprop

A friend of mine has a DJ250i but he is slightly east of Novato. Knows a thing or two about carbs. Send a PM if you want his contact info.
'We' like this' - Said by the one man operation.

Burnout

Bay Area Performance, Mountain View?
They don't call me Ironhead Rick just because I'm "hard headed"

Racepres

Quote from: JW113 on April 20, 2020, 01:50:05 PM
Bruce is long gone and no one took over his business. In fact, there is almost nothing left in the south bay area for HD oriented shops and even parts. Even half the HD dealers are gone now. Dudley Perkins HD is no more.

Drag strips are fine if you happen to live near one I guess. For me that would be Sacramento, 120 miles away. Personally, I find the plots of torque curve and AFR very informative. And not at just WFO.

-JW
If you have a Dyno Guy that shows stuff outside of WFO... you got a Good one... Most will Not/Can Not

JW113

You can use an eddy current dyno to put various loads on the motor at various speeds and throttle settings to get the AFR correct throughout the throttle range, as opposed to just acceleration the drum at WFO to redline, so the bike only runs well at WFO.

Right?

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Racepres

Quote from: JW113 on April 21, 2020, 07:42:26 AM
You can use an eddy current dyno to put various loads on the motor at various speeds and throttle settings to get the AFR correct throughout the throttle range, as opposed to just acceleration the drum at WFO to redline, so the bike only runs well at WFO.

Right?

-JW
If...and Only If 1] you have an Eddy Current Dyno, 2] If you know how to Run the Thing..
I have been tuning the Old Fashioned way for so very long... I will continue My Way..
Working my way from Idle to finally going to the Track [about 10 Miles] for 1/4 mile MPH at WFO..
Perfect??? Prolly Not, Effective??? Yup... Smooth as a babys butt, on my Test "circuit" around the local Lake!!!
It is Important that she work "smooth and even",  in 3rd gear too!!!!!

JW113

Although I do not take my bikes to the track, I've been doing the "butt dyno" also for 45 years. I don't have a problem with throwing a little technology at stuff once in a while. In fact am having fun with this DTT AFR I have hanging off this Ironhead. Not being a drag racer, have no time sheets or trophys for bragging rights. So what the heck, will maybe settle for dyno sheet.
:SM:

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

JW113

Well I've got 50-ish miles on it, mostly short little 10-12 mile spins on the freeway loop around San Jose, trying to keep it at a somewhat steady 65mph/3500rpm. Temps are around 70, so not too hot. Was puffing a slight amount of smoke initially when on the side stand, rev it and back off. But that seems to have cleared up so rings appear to be taking a set.

Have a tuning issue to work on, at the end of the run after it's fully warmed up it's picked up a blurbber when slightly backing off the throttle to get on a freeway connector and then back on the throttle. Like it goes lean for a bit. At steady speed, the AFR is on the high side of 14s to low side of 15s. I'm thinking that is probably a bit too lean for an Ironhead? I'll start with throwing some shims under the needle and see what affect that has.

The plugs look clean, white-ish, not burned, no oil or carbon fouling. Both heads read around 330degF after a test ride. Have not really given it much more than 1/4 to 1/3 throttle so far. I want to get 100 miles or so on it, then take out and do the 10 WFO pulls.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Burnout

You didn't give it a full 45° with the dual plugs, did you? I'd start at 36 or so and inch it up from there.
I recommend using a VOES too.

Today's gas doesn't put much color on the plugs and it's easy to get too rich looking for color.
A light grey ash kind of coloring I'd call normal.
I look at the plug threads and check how far the heat comes up the plug (3 threads is my target).
(depends on plug reach too as many use a 1/2" reach plug in a head that takes 7/16" reach)
and watch the ground electrode for blueing.

I'd shoot for mid 14's at cruise but you need like mid 13's if you roll into it. ~12.5 at WFO.

15's would be leaner than a pop corn fart.
They don't call me Ironhead Rick just because I'm "hard headed"

JW113

I rolled the timing plate back by ~5 degrees (one of the tick marks on the plate) before I started it, and also turned the advance mode switch back to "4" (S&S Hi-4N), so no, it's not at stock timing. By the way, the stock timing for this model is 40degBTDC according to the FSM.

The electrodes do not look like they've been hot, no discolor at all on them. After a quick swipe with a brush they look new. I agree, low/mid 14s is probably where it wants to be, now just how to get it there. I have 48 pilot jet in there now, I think the last time I tried a 50 it blacked the plugs in no time. But certainly could give it a try and see what happens. Since this stumble is happening at part throttle, with gentle feathering, I'm thinking more needle than pilot jet. At any rate, have some tinkering to do.

As interesting as this AFR is, I have to keep reminding myself "what would you do if you didn't have it?". Read the signs and make the adjustments, just like I've done forever. What I'm finding is the AFR is just reconfirming what the motor is telling me.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Burnout

Yep I know what you're saying, Motors talk to me.
Some people don't get it, I ride it and tell them it is too rich, they say it runs great.
Huh? It blubbers when you back out of it, it's too rich....
Or worse yet the opposite, it picks up when you ease out of it.....
Maybe it has to do with seat time or they are too busy looking at their reflection in the windows as they ride by.....   :bike:

Any Dyno or gauge based settings have to be verified/approved by the seat of the pants.

Yeah later models backed off the timing to 40°, even that is ridiculously high for a faster burn chamber.
It's amazing how much difference dual plugging makes on these motors.
Less timing, more power, better throttle response, easier starting and more.

Sounds like you have a good grip on it.
They don't call me Ironhead Rick just because I'm "hard headed"

Hossamania

Yes, dual plugs need much less timing.
If the government gives you everything you want,
it can take away everything you have.

JW113

Yep. The tricky part though is "how much is much less"? Lot of lore on the 'net that says 5 degrees less, but I don't know what the basis for that is. Just for fun, I looked up the timing specs for a 2000 XL1200S, which has dual plugs from the factory. A stock XL is 40deg, a 1200S is 20deg. Yes, that would be a lot in my book.
:SM:

So how to optimize on an old relic like this that's been converted to dual plug? I'm thinking put it on a dyno and start playing around with the timing. The limitation will be that playing with the timing by rotating the module affects both max timing, and timing at idle. The Hi-4N allows you to dial back the max timing, but only about 5 or 6 degrees. Dunno. I might have to break down and replace the module with a Dynatek or Ultima, which lets you make your own timing advance curve.

I went for another break in / tune loop, the AFR is now mid 13s to 14. Which is pretty much exactly what the WEGO instructions say to aim for. I have two shims under the N72S needle, seems to be right in the sweet spot now. With three shims it was mid to high 12s. While out riding, the WEGO started displaying Lb, which is low battery. Got it home, and sure enough the charge light is on. It lost the gene or regulator. Oh boy, one more thing to fix.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Hossamania

I remember talking to an old rider (like in his 60's!), a local independent shop owner, he mentioned the old Pans and Shovels needed their timing dialed back quite a bit when running dual plugs, I thought he mentioned by almost half. He was, maybe still is, a trials rider, a former club member, and quite the well known local character.
If the government gives you everything you want,
it can take away everything you have.

JW113

Quote from: Hossamania on April 23, 2020, 06:15:03 PM
I remember talking to an old rider (like in his 60's!),

Ouch! Hey I resemble that remark!
:SM:

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

turboprop

Quote from: JW113 on April 23, 2020, 04:48:56 PM

The limitation will be that playing with the timing by rotating the module affects both max timing, and timing at idle.

Yes, no and maybe. Have you considered the effect of different module positions in conjunction with the various curves and how they affect advance at idle and full advance?
'We' like this' - Said by the one man operation.

Racepres

Quote from: JW113 on April 23, 2020, 07:16:47 PM
Quote from: Hossamania on April 23, 2020, 06:15:03 PM
I remember talking to an old rider (like in his 60's!),

Ouch! Hey I resemble that remark!
:SM:

-JW

LOL
For Maximum Performance set the Timing where it Runs the Best... I will Not share where I ended up with the timing on the DragBike... but It also runs "Race Gas"... I never understood Why improve Performance with Dual Plugs... then throttle it with reduced Timing!!! All I ever got out of Reducing the Timing, was excessive Heat!!!
But... I hear it all the Time... We Ain't Racing Here... just Improving performance a Little bit I guess...
Edit; That Ironhead Still wants some Timing... It is still an Ironhead!!!!

Burnout

Dual plugging an Ironhead is not a little boost, it makes a significant improvement!

I'm sure the MoCo was aware of this and likely did not add this feature to production as a Sportster was already faster than a Big Twin (their flagship model).
If they had added it to production no one would ever by a Big Twin! (except touring guys who wanted a heavy weight bike)

Generally the high advance numbers that an Ironhead likes is due to to the crappy combustion chamber shape.
By dual plugging you are speeding up the time it takes to get the fuel in the chamber lit.
A motors need for high spark advance numbers is indicative of an in efficient combustion chamber
In the case of an Ironhead (which is an extreme example) it is so bad that a significant amount of the fuel doesn't get burned until it is way past the power making stage which contributes to the carbon buildup they are famous for.
There is a down side of the high spark advance numbers in that it puts the motor closer to detonating, combined with pockets of un-burned fuel which further increases detonation potential.
Dual plugging speeds up the peak pressure in the chamber by getting more of the fuel lit sooner, so technically the cylinder reaches peak pressure sooner it does not require near as much spark advance. This is beneficial as there are less cold spots in the cylinder and less tendency for detonation.
Detonation happens when the cylinder pressure has raised enough that the fuel ignites explosively. So you light the fuel on one side of the piston and the pressure starts increasing, the piston is still rising so the mechanical pressure is also rising. So by the time the fuel on the other side of the piston ignites the cylinder pressure has exceeded the fuels knock rating, and BOOM!
An great example of what happens is, a cap gun. If you ignite a paper cap in free air it burns like lighting a match, whoosh. But if you pressurize the cap by hitting it with a hammer it goes BANG!
(In the motor this all happens in microseconds so you have to "freeze frame" it to wrap your head around what is happening.)
For this reason you cannot compare the spark timing of a dual plugged motor to a single plugged motor
In other words by changing the spark advance you are adjusting the peak pressure timing, so technically the lower spark advance of a dual plug motor is not lowering the peak pressure. Dual plugging it advances the peak pressure so the spark has to be backed off to compensate.
Some motors with very efficient combustion chambers only need 20° of spark to make full power!
They don't call me Ironhead Rick just because I'm "hard headed"

Hossamania

https://youtu.be/jdW1t8r8qYc

I find this one fascinating, not dual plug, but related to engine spark.
Sorry if I'm hijacking. Not meant to change the discussion.
If the government gives you everything you want,
it can take away everything you have.

Racepres

Well I must have not got it all out of my Ironhead!!!!!
I can tell you that lots of advance at the start reduced at the top end is Very effective... not easy to do... but Effective..
And My Dual Plugged IH with a Healthy dose of Compression... wanted more timing than one would Think... to squeeze Maximum Performance..
75 Cu.In. doing 9.8 at 135MPH in a Standing Start Quarter Mile... In 1996!!!!

JW113

Well this has been an interesting day. Troubleshooting the no charge problem, so looked into the Ironhead spare parts box to see if I had a spare gene and regulator, but found a unopened box from JP cycles. Hmm, what have we here? One of those alternator conversion kits??? Don't remember ordering that, but like Hoss says, I'm old. Dementia setting in.
:hyst:

So spent the day putting that on, and now it seems to be charging again. Just for fun, weighed the diff between gene and alternator. 13.5bls vs 3lbs. Lighter is better, ja? So in the vein of weight loss, I ordered a Anti-Gravity battery, which is 10lbs or more less than this lead acid battery. Hey, less weight is HP, right?

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

turboprop

This the coolest ironhead I have ever seen and possibly my favorite thread right now. I really enjoy seeing these older bikes updated and modernized.
'We' like this' - Said by the one man operation.

JW113

Well I can certainly tell you that it's a real hoot to ride. Love those close ratio sporty 4 speed boxes. And I know the Prez don't like 16" front tires, but it sure changes the cornering characteristics for the better. I've had the battery on the charger for over a day, and it still will not get up to 100%. Starting to think that was my charging problem.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

JW113

I guess the battery is OK, finally charged up to the "green" zone. I use one of those X-treeme pulse chargers, this battery is old school lead acid and quite large at that. Maybe too much for the pulse charger. So no miles today but it was kind of warm here, like 88F. Rather do the break in when it's below 72F at the most.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Burnout

Quote from: Racepres on April 24, 2020, 11:00:15 AM
Well I must have not got it all out of my Ironhead!!!!!
I can tell you that lots of advance at the start reduced at the top end is Very effective... not easy to do... but Effective..
And My Dual Plugged IH with a Healthy dose of Compression... wanted more timing than one would Think... to squeeze Maximum Performance..
75 Cu.In. doing 9.8 at 135MPH in a Standing Start Quarter Mile... In 1996!!!!

Yeah, you need more spark when you're tipping the can!   :wink:
They don't call me Ironhead Rick just because I'm "hard headed"

Racepres

Quote from: Burnout on April 27, 2020, 08:19:23 AM
Quote from: Racepres on April 24, 2020, 11:00:15 AM
Well I must have not got it all out of my Ironhead!!!!!
I can tell you that lots of advance at the start reduced at the top end is Very effective... not easy to do... but Effective..
And My Dual Plugged IH with a Healthy dose of Compression... wanted more timing than one would Think... to squeeze Maximum Performance..
75 Cu.In. doing 9.8 at 135MPH in a Standing Start Quarter Mile... In 1996!!!!

Yeah, you need more spark when you're tipping the can!   :wink:


LOL... Legal Racing Gasoline... they dipped us every Pass!!!!! But, should one "Tip the Can" more lead yet is a requirement!!!!

JW113

My Anti-Gravity battery showed up this week, so spent the day putting that in and then some more break in miles. My god, the weight difference between the stock battery and the AG is off the charts. The AG feels like a little plastic box with nothing inside it. But I tell you what, it spun that motor over like the starter was on steroids. Wow. Might have to think about one for the RK now, which will barely start on a good day.

So I ditched the stock gene for a alternator, have the AG battery, am now pondering one of the Tech Cycle starters that use a Nippon-Denso gear reduction motor and are about 1/3 the weght of the stock Bendix. Weight reduction is good, yes?

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Hossamania

Weight reduction must be a very good thing, my doctor brings it up all the time. What's up with that?
If the government gives you everything you want,
it can take away everything you have.

JW113

Just remember the old rule of thumb when it comes to acceleration: 10lbs/HP. You can make the bike faster, and save money on food at the same time!
:hyst:

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Hillside Motorcycle

To install seals on those, you machine the guide prior to installation, and then modify the lower collar.
None leave here without that being done.
Otto Knowbetter sez, "Even a fish wouldn't get caught if he kept his mouth shut"

JW113

My machinist told me he was not able to add seals to the guides he used. He said between the already little space, and the higher lift cams, there was just not enough room. He did however use manganese bronze guides and clearanced the intakes on the tight side. So far it's not been a problem, it does not appear to be using oil and the plugs look nice and clean.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Racepres

Quote from: JW113 on May 11, 2020, 09:25:27 AM
My machinist told me he was not able to add seals to the guides he used. He said between the already little space, and the higher lift cams, there was just not enough room. He did however use manganese bronze guides and clearanced the intakes on the tight side. So far it's not been a problem, it does not appear to be using oil and the plugs look nice and clean.

-JW
Never been a problem on mine... Trust yer guy!!!

JW113

Yep, I do. He's a far better machinist than I. Although valve seals are nice to have, they are not a must have.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Hillside Motorcycle

Quote from: JW113 on May 11, 2020, 09:25:27 AM
My machinist told me he was not able to add seals to the guides he used. He said between the already little space, and the higher lift cams, there was just not enough room. He did however use manganese bronze guides and clearanced the intakes on the tight side. So far it's not been a problem, it does not appear to be using oil and the plugs look nice and clean.

-JW

The lower collar needs to be modified in a lathe, in order to install seals.
As I mentioned, we do that on every job here, and the lift of those cams is a non-issue.
:up:
Otto Knowbetter sez, "Even a fish wouldn't get caught if he kept his mouth shut"

Racepres

May 12, 2020, 07:32:09 AM #69 Last Edit: May 12, 2020, 08:07:47 AM by Racepres
Quote from: Hillside Motorcycle on May 12, 2020, 04:17:56 AM
The lower collar needs to be modified in a lathe, in order to install seals.
As I mentioned, we do that on every job here, and the lift of those cams is a non-issue.
:up:
If I was getting paid for it... I would do them all also... On My Bike, it ain't necessary...

JW113

OK, 400 miles of easy riding, today time to drop the hammer & dial in the main jet. I had a 185 in it, and first WOT's this morning was yielding 11.6:1 AFR. Too rich. I swapped in a 170, tested again, and now is around 12.2:1. Better, but will try a 165 and see what that gets. Trying to hit 12.6:1.

On thing has me a little confused. This thing is eating oil like crazy, like 2 quarts in 400 miles. And I can't figure out where it's going. It does not smoke at all, does not leak, exhaust does not stink like oil. I pulled the plug in the case, and got maybe 5 oz of oil. Dunno.
:scratch:

I pulled the plugs, they look 'OK', a little dark but I've see far worse. They look more like carbon from fuel than ash from oil. Looking into the plug holes, I can see the piston tops are still mostly shinny, not an oily mess. All I can figure is there is a bit of oil getting past the rings or guides and just getting burned. But don't understand why I can see or smell it.

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About all I can do for now is keep an eye on it, and the oil tank full.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

rigidthumper

Any drops on the case breather tube?
Ignorance is bliss, and accuracy expensive. How much of either can you afford?

JW113

I have the case vent into the air cleaner, with an in-line Krank vent valve. No oil up in the A/C or on the air filter element.

I made these just now. A trick I heard about long long time ago. Ironheads tend to get too much oil to the top end, they have two oil supply lines unlike Shovelheads. You can drill and tap one of oil line fittings to accept main jets, then restrict the oil flow. Maybe this will help. Or, maybe not...

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-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

JW113

Did a little more main jet tuning today. I thought I had a 165, but no. So I used a 160 for today's test. It must be awfully close, as the AFR is now 12.7 at WFO. I think I'll leave it for now, and let the dyno shop dial it in with better equipment. But it must be close, it no longer surges slightly when backing off the throttle from WFO.

And I think I've found a possible cause of the oil consumption. I think I'm overfilling the tank. This is the first XL I've owned with this kind of oil tank, and I think the oil cap on it is from a Shovelhead. The cap has a dipstick, but it does not match the picture in the owner's manual.

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The full mark on this dipstick is right up at the flange in the cap. In the manual, it appears further down, perhaps a half inch or more. Comparing where I've been filling the oil to, and where the oil tank vent line is on inside of the tank, I think I've been covering the vent hole with oil. I'm going to drop the oil and put in exactly 3 quarts, and see where that puts the oil level mark on the dipstick.

If anybody has a stock oil cap with dipstick, I'd sure love to see a picture of it.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Ohio HD

I don't have one, but I know they were longer that what you have there.


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JW113

Thanks Ohio! I just scored the gage rod from eBay. What parts manual is this from? Mine does not break out the individual filter cap parts like that.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Ohio HD

A '54 to '78 XLH/XLCH parts catalog


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