Jereme6655 Posted January 18, 2011 Report Share Posted January 18, 2011 so i just finished assembling my motor after having Jeff at FAST weld my crank and had him do a play/dune port on my cylinders after he bored and honed em out for a rebuild. First time i've ever split the cases on a banshee and things seemed to go pretty smooth and just wanted to make sure on what other people thought about my leakdown numbers.... pumped it to 6psi and let it sit for 6 minutes and it dropped 1 psi in the time period..... guess im just curious if these are decent numbers... Quote Link to comment Share on other sites More sharing options...
Phelps Posted January 18, 2011 Report Share Posted January 18, 2011 1psi drop is good to go! Quote Link to comment Share on other sites More sharing options...
Jereme6655 Posted January 18, 2011 Author Report Share Posted January 18, 2011 thanks phelps.......was hopin someone like a more well known hq member would stick there dick out and answer....hahahaha thanks man... Quote Link to comment Share on other sites More sharing options...
Phelps Posted January 18, 2011 Report Share Posted January 18, 2011 Yea like stated 1psi drop is def no Good, Is the motor back in the bike yet?? You could start it and try and track the air leak, or strip errr down and do it all over again. If you have a cool head it could be something as simple as a small oring, has happened a million times. Joe huh? i just posted it was fine. my info coming from a sponsor. and what does well known have to do with anything? Quote Link to comment Share on other sites More sharing options...
uhoh0573 Posted January 18, 2011 Report Share Posted January 18, 2011 as phelps said... 1 psi in 6 mins is PERFECTLY FINE. the rule is 1 psi in 6 mins. no more. Quote Link to comment Share on other sites More sharing options...
Jereme6655 Posted January 18, 2011 Author Report Share Posted January 18, 2011 huh? i just posted it was fine. my info coming from a sponsor. and what does well known have to do with anything? haha...yea i understood you were sayin it was fine. what i meant by more well known was that youve been on the hq for awhile and have been around these bikes longer than i have......so someone with more experience than me hahaha Quote Link to comment Share on other sites More sharing options...
wacko2000 Posted January 18, 2011 Report Share Posted January 18, 2011 Sorry for the confusion, not sure what you are talking about, as far as being well known bc I didnt say anything along those lines. But i was always under the impression that if it moved especially 1psi that it was not good, But guess thats good news bc we have done a few leak downs on my friends bikes, and we where concerned if it moved as much as 1 psi.. So for the record, 1psi drop is nothing to be concerned about?? Quote Link to comment Share on other sites More sharing options...
uhoh0573 Posted January 18, 2011 Report Share Posted January 18, 2011 use the search function, there are TONS of topics on it. Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted January 19, 2011 Report Share Posted January 19, 2011 I like to pump it up to 70psi. Quote Link to comment Share on other sites More sharing options...
tedd1 Posted January 19, 2011 Report Share Posted January 19, 2011 Sorry for the confusion, not sure what you are talking about, as far as being well known bc I didnt say anything along those lines. But i was always under the impression that if it moved especially 1psi that it was not good, But guess thats good news bc we have done a few leak downs on my friends bikes, and we where concerned if it moved as much as 1 psi.. So for the record, 1psi drop is nothing to be concerned about?? Depends on where it is leaking, IMHO. Quote Link to comment Share on other sites More sharing options...
J-Madd Posted January 19, 2011 Report Share Posted January 19, 2011 Depends on where it is leaking, IMHO. Good point. If is around a crank seal, it could possibly get worse. If its around the intakes and you can't get it to stop, it's not likely that it will get worse. That being said: If it leaks down to 2 lbs in 6 mins I still run it; even if it's the crank seal. You can tell by the sound of the engine if it's gotten worse. Quote Link to comment Share on other sites More sharing options...
Jereme6655 Posted January 19, 2011 Author Report Share Posted January 19, 2011 you run a motor that dropped from 6psi to 2psi? so you run your motors with a 4psi pressure drop in 6 minutes? wow.......no offense but i don't wanna trust that...hahaha. mine dropped from 6.5psi down to 5.5 psi in the 6 minute period. i've heard that you can lose up to 2psi in 6 minutes...but i don't wanna even lose that. Quote Link to comment Share on other sites More sharing options...
gotta_goatsfast Posted January 19, 2011 Report Share Posted January 19, 2011 Where are the common places air will leak from? I will caution that some might have false or mislead pressure drops due to poor sealing of the exhaust plugs or where the leakdown tester clamps to the intake. Quote Link to comment Share on other sites More sharing options...
J-Madd Posted January 19, 2011 Report Share Posted January 19, 2011 you run a motor that dropped from 6psi to 2psi? so you run your motors with a 4psi pressure drop in 6 minutes? wow.......no offense but i don't wanna trust that...hahaha. mine dropped from 6.5psi down to 5.5 psi in the 6 minute period. i've heard that you can lose up to 2psi in 6 minutes...but i don't wanna even lose that. I don't prefer a leak that bad, but I do have one together right now that won't hold but about 2, maybe 3 psi after 6 mins. It's a 16 mil Twister in stock cases. Lots of case work and I've sealed up all the leaks I can find. Intakes (POS UPPs) are usually the culprit - which I've got some Chariot billet ones for next season. Other places they leak are around the key way of the primary gear on aftermarket cranks or on straight cut gears. Difficult to stop those, even with yamabond. Quote Link to comment Share on other sites More sharing options...
Jereme6655 Posted January 20, 2011 Author Report Share Posted January 20, 2011 gotcha.....so its a drag motor...haha......i was gonna say SHIT...you wont catch me riding that thing more than 2 blocks from our cottage. But its a little bit different if its a drag motor......not so much when it comes to having to do a rebuild....but definately makes a difference on how far you have to walk back to camp lol Quote Link to comment Share on other sites More sharing options...
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