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Troubleshooting my new 4mil build


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3 minutes ago, hercalmighty said:

125 psi? Either you have a bad tester or something is screwed up. Did you check your squish?

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tester should be good. Ill let you know about compression in a couple hours since the rings should be seated. I havnt checked the squish other than I know the pistons dont touch the domes but maybe at higher rpms they would? if my squish clearance is off, how do I fix that? i have the stroker domes and the 795 pistons. would my base gasket be the issue?

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Doesn't matter if the rings are sealed you aren't getting an extra 40 psi from sealed rings lol. There is your problem without a doubt.
During the test your are holding the throttle wide open and kicking the hell out of it until the needle stops?

Edited by Ayesully810
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5 minutes ago, Ayesully810 said:

Doesn't matter if the rings are sealed you aren't getting an extra 40 psi from sealed rings lol. There is your problem without a doubt.
During the test your are holding the throttle wide open and kicking the hell out of it until the needle stops?

yup, kicking the crap outta it at wot. im going to pull the head off and see if i can see anything in there. Ill comp check it one more time first to make sure Im giving you accurate numbers

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Agree with above, you need to check the squish clearance as this may indicate some of what is going on.  Beyond that, it might be wise to pull the head and verify the exhaust height so the duration can be determined.  

It sure sounds compression related though.  Wrong pistons or wrong domes.  

 

You also mention having detonation issues.  That can happen with very loose squish due to the flame front pretty much exploding, rather than getting a centralized controlled burn.  You should NOT be having detonation issues with that setup, and timing can easily go beyond 4*.  

 

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4 hours ago, Ayesully810 said:

again?

what was it when you checked it after the re build?   You should be at least 170 psi in each cylinder with compression with that 110 gas. If not that will explain a part of your problem.  Carl does top notch work.

Ok so we just comp checked it, it's at 175+ for both cylinders, passed the leakdown test holding 6lbs for over 6 minutes. 

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My travel season is over and I will gladly take the bike and figure it out for you. Me personally would run shearers on that set up the lrd could be heat soaking the cylinders  or incorrect signal which would explain why you could throw 410s at it and it still be lean . I have done 100s of 4 mill stockers and never had anyone disappointed with port work so I would love to see what the deal is. I also have every pipe known to man on hand so I can see what works best. I feel for you . 

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Sleeper, I agree that pipes may be causing some issue here but we built several for guys running those and never had one produce "no more power than it did before".  I really think the squish and ex duration needs checked.  It could  be that the duration is so wild that those pipes will never work right.  Or it could be a really piss poor dome setup.  All I know is it would be hard to throw a 4mil crank and porting at an engine and NOT make more power, even by accident!  

I suspect you or someone experienced could just take a rip on the bike and figure out what is going on.  

I remember several coming in the door that were actually massive clutch slip problems!  You can't run a 4mil on the stock clutch setup.  I also remember a guy bringing us a bike because no one could figure out a "clutch slip" problem.  That one was actually tires spinning on the wheels!  He had ag bike tires on it.  

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24 minutes ago, blowit said:

Sleeper, I agree that pipes may be causing some issue here but we built several for guys running those and never had one produce "no more power than it did before".  I really think the squish and ex duration needs checked.  It could  be that the duration is so wild that those pipes will never work right.  Or it could be a really piss poor dome setup.  All I know is it would be hard to throw a 4mil crank and porting at an engine and NOT make more power, even by accident!  

I suspect you or someone experienced could just take a rip on the bike and figure out what is going on.  

I remember several coming in the door that were actually massive clutch slip problems!  You can't run a 4mil on the stock clutch setup.  I also remember a guy bringing us a bike because no one could figure out a "clutch slip" problem.  That one was actually tires spinning on the wheels!  He had ag bike tires on it.  

 

1 hour ago, ginger said:

i ran LRD pipes on my stock cylinder 4 mil with no issues. 

 

 

2 hours ago, sleeper06 said:

Have you tried adjusting the pipes?

 

2 hours ago, sleeper06 said:

My travel season is over and I will gladly take the bike and figure it out for you. Me personally would run shearers on that set up the lrd could be heat soaking the cylinders  or incorrect signal which would explain why you could throw 410s at it and it still be lean . I have done 100s of 4 mill stockers and never had anyone disappointed with port work so I would love to see what the deal is. I also have every pipe known to man on hand so I can see what works best. I feel for you . 

I solved the problem last night. Noss sent me blaster cut stroker domes instead of banshee cut domes. They were way too deep! Unfortunately, while trying to set up jetting with the screwed up domes, I melted an electrode on my plug which screwed up my ported stock cylinders...  Soo my serval cylinders are on order now lol. Thank you guys for all the input! Me and Carl are going to make a day of tuning the bike when I get the serval installed!

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Oh boy you had me scratching my head like wtf. I'll take those cylinders back if there useless to you. I will tell you this those cylinders correctly set up will outrun a serval.  Brandon the duration was 195-196 with 35 blowdown, not optimal for that pipe but I've used them before also. What really got me was how he said the gear revved instantly and I know with my porting and those blowdown numbers it should feel like turbo when it gets on the pipes and over rev better than most. It just sucks you never got to see the full potential of those cylinders .

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