HarleyTechTalk

QuoteLOL! I bet you're also well-schooled in the "theory of constraints" 

somewhat ,but always  to learn the hard way 
here's one I was told to ask you about awhile back.
I didn't want to waste your time ,until it was ready to come to pass.

so here is my question ,speaking of constraints.
1250cc your XB heads (stage 3) cranking 180 ccp (reverse dome) ,making 100 hp with SE HO 575 cams.
super G carb. total seal rings.
I am putting it on the bottle.
#1 total seal rings, is it a must they be replaced with something a little more nitrous friendly.
#2 looking to go 30-50 hp . is 50hp achievable ? or disastrous

Quote from: strokerjlk on December 24, 2013, 10:20:33 AM

QuoteLOL! I bet you're also well-schooled in the "theory of constraints" 

somewhat ,but always  to learn the hard way 
here's one I was told to ask you about awhile back.
I didn't want to waste your time ,until it was ready to come to pass.

so here is my question ,speaking of constraints.
1250cc your XB heads (stage 3) cranking 180 ccp (reverse dome) ,making 100 hp with SE HO 575 cams.
super G carb. total seal rings.
I am putting it on the bottle.
#1 total seal rings, is it a must they be replaced with something a little more nitrous friendly.
#2 looking to go 30-50 hp . is 50hp achievable ? or disastrous

Well, first of all, on this engine kit, did it come from us or from the other guys? And did these rings actually come in a TS box or were they just said to be TS rings? Conventional or gapless?

I won't speak for the other guys ... but I'll say this ... the vast majority of the rings we sell with our engine kits come with rings we get from our pistons supplier, CP, not from TS. CP gets them from multiple sources.

However, that said, you see a lot of the same markings on rings of different brands. Many rings come from company "N". Again, not my place to comment on what other people do, but bear this in mind. What it says on the box doesn't necessarily matter.

Anyway, with a 30hp shot, for reasonably short periods of time, you probably won't get into trouble on conventional ring gaps. As you raise the cylinder pressure and heat, though, it's good to open it up. You don't want to butt rings, it can make a mess.

I used nitrous at the salt flats for many years before I made the switch to nitro. It's a different environment, we'd lean on the button for miles at a time. Getting it to stay together is the name of the game.

Nitrous is a bit like hitting the top of the piston with a hammer. It's a hard, fast burn with a very high peak pressure. Take timing out and tighten up plug gaps, especially at 50hp. Also, I found I could run it quite a bit fatter than conventional wisdom would dictate, and still make a mountain of power, and the pistons would live longer. Thermal barrier coatings also extended how far I could push it. Lowered ring packs and the correspondingly thicker floor in the valve pockets helped a bunch. If you're still hurting pistons, lower the CR. I've seen nitrous bikes that make about 1/3 the power on the motor as on the button, if you can believe that.

But even doing all that, I more or less hit a durability wall, where I just couldn't make more without breaking pistons. Nitro immediately moved that wall for me. Fastest we ever went on nitrous was about 210 (on 100ci). Very first time out on the nitro we went 218 and didn't break it (well, not on that pass anyway). That was an eye-opener. The dyno didn't tell me it was going to run that fast. Load sensitive fuel and all that.

Here's an 82" Bonneville motor I ran once many years ago ... not really optimized for the bottle, as you can see it has a decent all-motor number ... but this motor was pretty durable, until the day it stuck a Carillo out the front ...

yes it was the other guys. motor is from 2006. I was told you did the heads .
the racer I bought the bike from mentioned in 2010 he re ringed it with T/S
your advice sent me to the folder with all the specs. this is what I found.
thanks for you input.
I will start out small 20-30 hp.
if i were to go two stage with a 20 hp hit and bring the other 20 hp in on time ,would that be any easier on things?
I will have to get a hold of the previous owner ,and see if indeed the rings are .006 gap
thats a killer 82er

Refreshing topic here, fella's. Stroker, how are you going to handle the tuning part? Are you running EFI or carby? Id be lying if I said I wasnt jealous.  Ive been wanting to build a small and idiot proof DIY NOS kit for the masses. I have a pretty good plan... I think... but these new cranks are a little bit scary from a liability perspective and piston to cylinder clearance and ring gaps have to be considered, obviously. A safety switch that would only allow a precisely metered dose with a timer to only allow so many hits per X amount of time would be something to consider. The tuning, I think I have a good handle on that part after some thought on wet vs dry setup and visiting with Clark at Hemrick Performance and the way the kit itself needs to be designed; I have a pretty good hunch on the way that needs to work but might be a hard sell even though its cheap horsepower and its only hard on the parts when you lay on the button vs a radical NA motor that beats on parts every time it turns over. NOS got a bad wrap when it was harder to precisely deliver the correct dose of the NOS and the fuel and the ports may not have been ideal to prevent puddling but I think with todays EFI systems, tuners, and injectors atomizing the fuel nicely right behind the valve, they stand a much better chance on not melting down. Hey, you know what they say, lean makes good power... right before it burns up... 

[attachment removed after 60 days by system]

After enough fuel, and retarded spark, the next safety factor is never use it below about 3,000 RPM.
Remember, a "30 hp shot" doesn't add 30 hp.
It adds 30 ft/lbs, and at low speed that's like double the cylinder pressure.

Quote from: panic on December 24, 2013, 09:38:22 PM
After enough fuel, and retarded spark, the next safety factor is never use it below about 3,000 RPM.
Remember, a "30 hp shot" doesn't add 30 hp.
It adds 30 ft/lbs, and at low speed that's like double the cylinder pressure.

thanks
I launch at 5750 rpms. I wont be bringing the spray in until 2 nd gear ,and then on time after the shift..
nothing under 4200-4500 rpm's.

We always run a switch so that the solenoids are only powered at WOT, panic is on target here, IF the blade closes and the juice stays on, some thing is fixing to blow..KABOOM

http://www.dragzine.com/features/video-features/video-five-spectacular-drag-racing-nitrous-explosions/

You guys are all exactly correct, always have the throttle wide open and never get into the button from low rpm, those are both golden rules of using nitrous!

With respect to the progressive controller, I used a Schnitz for years, partly to help control wheelspin (a huge problem on the salt), but also a number of people told me that it's easier on the motor to bring it in slowly. I could never really prove that one way or the other though. The box finally gave up the ghost and honestly, I didn't really miss it, it's reasonably easy to control the wheelspin by feathering the button. It's not like drag racing, where you're busy shifting and the like, we don't even get into the button at all until we're in top gear. The rider has time to watch the tach and concentrate on body position and modulate the button as needed to keep it hooked up.

Quote from: aswracing on December 25, 2013, 07:27:24 AM
You guys are all exactly correct, always have the throttle wide open and never get into the button from low rpm, those are both golden rules of using nitrous!

With respect to the progressive controller, I used a Schnitz for years, partly to help control wheelspin (a huge problem on the salt), but also a number of people told me that it's easier on the motor to bring it in slowly. I could never really prove that one way or the other though. The box finally gave up the ghost and honestly, I didn't really miss it, it's reasonably easy to control the wheelspin by feathering the button. It's not like drag racing, where you're busy shifting and the like, we don't even get into the button at all until we're in top gear. The rider has time to watch the tach and concentrate on body position and modulate the button as needed to keep it hooked up.

right now I am capable of controlling with the Dynatek setup,and a WOT switch . RPM only.
I plan to use a Daytona sensor NC-2 progressive controller. this way I can use gear/rpm/time. for two stages if desired .
also will be able to kill the nitrous and ign for the air shifter. (time/rpm)
seeing as i already have a couple wego's ,I can utilize the data logging at the track or dyno.
all in conjunction with a lean out switch .
not so much worried about the tuning ,as i am the rings.

All that sounds great.

But fuel motors are brutal on pistons. Getting the pistons to live is always my big challenge, whether nitrous or nitro. You can only build so much cylinder pressure before you melt something down. Nitrous is great fun and much more practical than nitro - it's not nearly the hassle - but the long, slow burn of nitro lets you take things much farther before you hit the breaking point. But it's a big-ass hassle, too, between having to start it on methanol and constantly changing the oil.

Quote from: aswracing on December 25, 2013, 10:33:59 AM
All that sounds great.

But fuel motors are brutal on pistons. Getting the pistons to live is always my big challenge, whether nitrous or nitro. You can only build so much cylinder pressure before you melt something down. Nitrous is great fun and much more practical than nitro - it's not nearly the hassle - but the long, slow burn of nitro lets you take things much farther before you hit the breaking point. But it's a big-ass hassle, too, between having to start it on methanol and constantly changing the oil.

nitro wasn't in the cards for this year. not enough money,is the biggest reason.
maybe with some sponsorship  support. but it still takes much more people  support to run a nitro bike.
tow vehicle, starter cart , and people to help run them .
going to go easy ,and try not to break parts.

I remember the very first time we hurt a piston on nitro ...

We made a pass, and got a bunch of nitro laden oil out the breather. Up until that point we had just been getting a small amount of clear liquid.

We pulled it down and at first glance, we didn't see anything wrong. Piston wasn't broken or scuffed. Hmm.

Then we noticed that we couldn't move the top ring. The cylinder pressure had literally shoved the crown of the piston down and it was holding the top ring like a vise.

But there were plenty of times we ended up scuffing them, or melting them, or breaking them. Here, I have an interesting picture ...


Check out the top ring groove. Pulled this one out in the nick of time.


Piles and piles of pistons that look like this, from both nitrous and nitro. You want to play with fuel motors, just consider them a consumable

So Jim, EFI or Carb? Wet or Dry?   

ASWRacing what do you think about running a wet kit( say around 40-50 shot)on a efi bike? putting nozzle in the intake pointing at the valve ? also good reading here btw

Quote from: WideWildGlide on January 06, 2014, 05:27:13 PM
ASWRacing what do you think about running a wet kit( say around 40-50 shot)on a efi bike? putting nozzle in the intake pointing at the valve ? also good reading here btw

Sorry, didn't mean to ignore you, I've just been to f'ing busy to participate here much lately. Seems like the busy season is starting early this year.

To be honest with you, I've never bottle fed an efi bike. Just thinking about it though, I can see a couple of challenges. One, you need the ability to pull timing when you're on the button. Maybe there's a way to rig it up where you rail the MAP sensor input and set up that column for the timing to be backed out? I don't know, is there a better way to do it? The other concern I can see right off the top of my head is fuel supply. I don't think you'd want to tap into the high pressure line from the tank ... it's in the range of 50psi typically and the nitrous nozzles I've worked with wanted about 8psi and have their own pump. So a second tap from the bottom of the tank would be needed, gravity fed to the nitrous system's pump. Unless again, there's a better way to do it?

The car guys have no doubt solved these issues. Hell, maybe the ricer racers have as well. I'm just ignorant on the whole thing. All my experience has been with carb'ed motors. Maybe someone who knows the best approaches will chime in.

Quote from: aswracing on January 10, 2014, 12:11:01 PM

Quote from: WideWildGlide on January 06, 2014, 05:27:13 PM
ASWRacing what do you think about running a wet kit( say around 40-50 shot)on a efi bike? putting nozzle in the intake pointing at the valve ? also good reading here btw

Sorry, didn't mean to ignore you, I've just been to f'ing busy to participate here much lately. Seems like the busy season is starting early this year.

To be honest with you, I've never bottle fed an efi bike. Just thinking about it though, I can see a couple of challenges. One, you need the ability to pull timing when you're on the button. Maybe there's a way to rig it up where you rail the MAP sensor input and set up that column for the timing to be backed out? I don't know, is there a better way to do it? The other concern I can see right off the top of my head is fuel supply. I don't think you'd want to tap into the high pressure line from the tank ... it's in the range of 50psi typically and the nitrous nozzles I've worked with wanted about 8psi and have their own pump. So a second tap from the bottom of the tank would be needed, gravity fed to the nitrous system's pump. Unless again, there's a better way to do it?

The car guys have no doubt solved these issues. Hell, maybe the ricer racers have as well. I'm just ignorant on the whole thing. All my experience has been with carb'ed motors. Maybe someone who knows the best approaches will chime in.

no worrys, im just grateful that you and others that have experience share it and express what you know with  everyone and me, i was think about putting a T in the crossover line on the Dyna gas tanks(always going to strip with full tank and using a stand alone fuel pump that how i was think about getting the fuel from on a efi bike instead also this would just be for friday night drag strip duty for now so i could have a map tune for nitrous and with out and just change the maps over at the drag strip and afterwards i could pull everything off and replace cross over line and plug the foggers/nozzle. its just i really like the idea of a wet kit when talking about 50 shot vs dry 50 shot,