'98 Sportster w/ 1200 kit (Loud Knocking)

[HotfuzzMurphy]

Just bought this '98 Sportster and it was riding very well once I got rid of the Autolite spark plugs and replaced them with Champions. 
Later that evening cruising across a bridge it just suddenly started knocking very loud, gave me a little shake and died. 
It starts up still easily but the knock is very loud and doesn't sound very good at all.
Narrowed down the sound ish.  Maybe a rod?  cam?  valve?
It's my first bike, and I'm not an expert.  Any thoughts?

[HotfuzzMurphy]

Found out it has adjustable push rods.

Sent from my XT1254 using Tapatalk

[HotfuzzMurphy]

Just bought this '98 Sportster and it was riding very well once I got rid of the Autolite spark plugs and replaced them with Champions. 
Later that evening cruising across a bridge it just suddenly started knocking very loud, gave me a little shake and died. 
It starts up still easily but the knock is very loud and doesn't sound very good at all.
Narrowed down the sound ish.  Maybe a rod?  cam?  valve?
It's my first bike, and I'm not an expert.  Any thoughts?

Found out it has adjustable push rods


Sent from my XT1254 using Tapatalk

[Panzer]

Murph, just wondering, is it a 1200 or an 883?
With the bike at idle, does it still bang?
Can you see if the noise is coming from the front of the engine or back.
Have you checked it over for oil levels in all three places?   (That should have been done first)

Need some answers before we can help further.  >>> Standing by for your response!

Panz

[HotfuzzMurphy]

Oil levels were fine.
The noise was coming from the front.
The bike was originally an 883. It has a 1200 kit. 
And yes sir. It bangs at idle as well.

Sent from my XT1254 using Tapatalk

[Panzer]

Since you determined that the push rods are adjustable, I suspect you are can to turn wrenches.
If so, I'd think about getting into the front cylinder before damage happens or first get proper adjustment on the push rods.
Did you get and details from the previous owner other the a 1200 kit being installed and who did the work?
I'm still with you on this.
Need some history though.

Panz

[HotfuzzMurphy]

Nope. The guy who did the work sold it to the guy I bought it from. I adjusted the pushrods slightly. Gonna try this real quick. I have a technician working with me but we didn't go lower than getting the rods out and checking them out.

Sent from my XT1254 using Tapatalk

[Panzer]

You working on it now?
Keep me informed of what you're both doing and I'll try to help you find the problem.
There is plenty of help here besides me.

[HotfuzzMurphy]

Yes sir. Just getting it back to see how the adjustment on the rods fairs.

Sent from my XT1254 using Tapatalk

[Panzer]

Good.....I'm here.

[Panzer]

I don't think that's gonna be your problem but, I've been wrong before. 

[HotfuzzMurphy]

Thank you.

Sent from my XT1254 using Tapatalk

[Panzer]

Welcome.......still here.
Anything new?    Noise?

[HotfuzzMurphy]

Calling it quits tonight. Got it top dead center. Zero valve lash. The intake rod is right and difficult to rotate with my hands.
Now thinking cams/lifters

Sent from my XT1254 using Tapatalk

[Panzer]

Must go out of town Sunday and Monday, will check back Mon. night.
Good luck.

Anyone else want to chime in with Murph's problem.......step up.

[HotfuzzMurphy]

Thanks man. I will keep updating as we figure it out. Getting up early for it.

Sent from my XT1254 using Tapatalk

[Panzer]

Hi Murph,
You might want to read the link below about an HTT member that had a similar problem you are having.
Read it in it's entirety, you will understand it better and to what your problem might be, before you tear down.
I'll be back to see your update.
Again.......good luck.
                                              http://harleytechtalk.com/htt/index.php/topic,83610.msg937608.html#msg937608

[HotfuzzMurphy]

Thank you again.
And so we took a look at the cams.
They're D cams. But my service manual says to only use W cams.
And the exhaust valve looks a little off. And the timing is top dead center.
The exhaust valve lifter is down further than the rest and no play to lift it back up.

Sent from my XT1254 using Tapatalk

[Hossamania]

Perhaps that lifter has collapsed.

[aswracing]

And so we took a look at the cams.
They're D cams. But my service manual says to only use W cams.

91-06 883's all came with "D" cams
91-03 1200's all came with "D" cams, except the 98-03 1200S Sport model
98-03 1200S Sport models came with "W" cams
04+ 1200's all came with "W" cams
07+ 883's all came with "W" cams

Bottom line, your bike being a '98, and not being a 1200S model, it came with "D" cams.

And the exhaust valve looks a little off. And the timing is top dead center.
The exhaust valve lifter is down further than the rest and no play to lift it back up.

Keep in mind that there are two TDC's, one at overlap (both valves are slightly open) and one at the top of the compression stroke (both valves fully closed). Don't get fooled by looking at the valvetrain at overlap TDC.

Second, if the lifter is farther down in it's bore than the others, about the only thing that can be is if the roller has an issue.

Hopefully you pulled the rocker box before you pulled the cam cover, so you didn't put valve spring pressure onto cams that are only supported on one end.

[hogpipes1]

Thank you again.
And so we took a look at the cams.
They're D cams. But my service manual says to only use W cams.
And the exhaust valve looks a little off. And the timing is top dead center.
The exhaust valve lifter is down further than the rest and no play to lift it back up

The D cams are stock for 883/1200   the W cams was used in the hot rod 1200S  ( sport)  bikes and  comes with 2 plugs in ea. head.

[HotfuzzMurphy]

Okay, so measuring the D cams, the intake cams are not the same size, one is ever so slightly smaller.  Same with the exhaust cams. 

[Panzer]

Any further report on this bike?

[HotfuzzMurphy]

Well my truck broke down. So I had to fix that.
Looking to get back at the bike today.
Going to check the pistons and valves.
Either way I'm going to replace the rods and cams for sure.
Just hoping the pistons aren't damaged. I found some notes from the previous owner of the guy I bought it from.

Sent from my XT1254 using Tapatalk

[HotfuzzMurphy]

Sent from my XT1254 using Tapatalk

[Panzer]

Yea gads.
If I'm reading his note pad right, there's .010 over pistons in 1200 cylinders and 883 heads? 
Am I correct on that, or did I miss read?
I believe he said a low mileage 883 cylinder head......I don't understand that. 

[HotfuzzMurphy]

Yes sir you read that correctly.

Sent from my XT1254 using Tapatalk

[Panzer]

  Good luck with the mismatched parts.
Let us know how it goes.

[Jammer53]

So let me get this straight. The guy you bought this bike from screwed up the motor, and sold it to you that way without saying anything about it.

That about sum it up?

If so, I'd hand him the bill for all repairs and if he doesn't pay it, take him to small claims court.  And an "as is" bill shouldn't exonerate him if he KNOWINGLY sold you a bad bike.

Jim

PS: I'm not now nor have I ever been a lawyer, nor did I ever play one on tv. 

[HotfuzzMurphy]

I hope he didn't know about all this.
But we are catching part of this hurricane so I haven't been able to do anything further on it.

Sent from my XT1254 using Tapatalk

[Hossamania]

Even if he did know about the mismatched parts, "as is" is just that. Buyer beware.

[Tom Hockenberry]

I don't get it, but a 1200 if you want a 1200. Give the 883 to the old lady, gears suck anyways.

[xlfan]

Yea gads.
If I'm reading his note pad right, there's .010 over pistons in 1200 cylinders and 883 heads? 
Am I correct on that, or did I miss read?
I believe he said a low mileage 883 cylinder head......I don't understand that. 

I think the notepad from 2010 states that the original 883 rear head got damaged by detonation caused by the 1200 flat tops in and already done 883/1200 conversion, hence the new used 883 head, and this time with the correct dish top 883/1200 conversion pistons.