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Discussion Starter #1
Me and my friends were talking last night about my V. They seem to think that if I were to put a thinner head gasket in it, I would greatly increase the overall HP. I was thinking there might be some clearance issues, but they seem to think there is room to allow for the thinner gasket. They said that my bike starts way to easy to not be able to put a thinner gasket on. What do you all think? Ever tried changing them out and see better HP results? They said that I might see 25-30 HP increase by using a thinner gasket.

They also said that by using the propper gasket - not sure what that is yet - that I could then go up even more with the nitrous. So I'm curious about that to.
 

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25-30? impossible, thinner head gaskets just raise compression a little, would even notice an increase in power most likely
 

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um... NO... and stop listening to your friends... or stop drinking and listening to them.
 

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trust me.. that is a lot of fun.. :lol:


heck, it is fun doing it on a bike you don't even own too....:wub:
 

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Discussion Starter #7
These guys have been racing for a long long time. Seem to know what they are talking about. But you guys do to. He seriously thinks I'll get a lot out of just changing the head gaskets.

I got to do something. Stip the bike down to nothing but frame and motor, or turbo, or super charger, or more NOS. Something. I still got my azz handed to me by these damn banshees even with a 50 shot. That just don't seem right.
 

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What's your compression now? The HP gain would be very minor, if any. Not worth tearing it down and potentially running into clearance issues.

25-30... no wayyy
 

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Discussion Starter #9
Just got off the phone with Jesse - my friend. He is running a Suzuki GS1150 that now is a 1640. He said they went down 20 thousandth on the gasket and it made a hell of a difference. Noticeable difference.

He wanted to know what my cam lift and duration is. I have no idea. Just whatever Mickey put in there and uses. Does anyone know what that is?
 

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Just like they said above your only going to gain compression from a thiner head or base gasket. I have heard if you can get your valves to just "kiss" the piston they will put out better power. I heard this from a master mechanic. Idk about 25-30 HP gain but who knows. This would be worth testing.
 

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One of our lt 80s I put together and mr forgot to put the head gasket on. It is a little faster than the other 2 but not a huge difference. I know it's a 2 stroke and a much smaller motor, but the results should be about the same as ours V's. Of course you will have more compression but the hp gains would be very minimal. I doubt you would even be able to feel a difference.

I have a 79 GS 1000 and it is FUN. Brought it back to life after sitting in a field for 6 years. I only spent $300 total to get it roadworthy. If anyone wants a streetbike for cheap these are great machines and super cheap to get in to, and there are parts everywhere. I bet his 1640 is BADASS!
 

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The only person I would trust with your question is Mickey. VFJ might also know but I'm not sure.
You may end up having issues with the head gaskets because of the higher compression and Nos combined even if the clearance is safe.
 

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don't know what they are basing those extra hp values on Chris.

B f*cking S. lol

If you remember that's the way Ray had my 800 set up, heads shaved down so much, to increase compression, the valves were just kissing the piston....it was more like a french kiss:rolleyes:

You may gain a few extra IF you have the clearances to do it.

There is only so much compression you can get out of these because of the design. Take Glenns Keller molded pistons. They digitally render the combustion chamber, then machine the dome of the piston to match it. After you cut valve pockets and stuff.....that's all you're gonna get out of them.
 

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No good on thinner gaskets.
It will def leak blow and suck:rolleyes:
Deck the heads--no problem.
Thinner gaskets--not a good idea.
800`s have a head gasket seal issue to begin with
[unless the sleeves are in perfect] that a thinner head gasket would make leaks more possible.
go with ,,,,,what works.:)
Want more power?
---coin up a blower/turbo/bigger cc.
higher comp pistons and bigger valves.:D
 

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Your friend is wrong. I don't mean to be disrespectful, but does he realize its not a 1700cc four cylinder drag bike engine? 30hp is probably a 25-30% HP increase.

The problem is that you need to look at more than just a head gasket. Take into account, your deck height. With the compression distance Mickey uses, your piston should be at or near zero deck. Meaning it is not down in the cylinder much at TDC. Using a .040" thick head gasket gives you the proper amount of quench area between the piston and the deck of the cylinder head. Cutting the gasket down makes it too close, and you will most likely hit the piston on the head. It's not a piston to valve clearance issue, so cam duration, and lift have no rendering on this part of the process.

I have ran engines at .037, and have had them just touch, and others at .045, and they show no signs of touching the head. Not every one is going to be the same, as my skirt profile is different from Mickey, and Ray's, but they are all pretty similar.

As far as HP, you might get a little from added compression, but there are better ways to go about it.
 

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Whew... Glad you stepped in Glenn. I was about to say the same thing. :hehe:
 

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I think the FST 800 has to have 3 layer gaskets,the piston is designed to use it you dont want to mess with that,you need to call Mickey and get the 13.1 gas ported 800 piston,I ran those and the stage 3s last year on laky and a 30 shot boondocker kit and ran 4.5s on a Brute,and I had been running the 11.1 and was in the 4.7 4.8 and also I was running race fuel with the 11.1 and not alky.
 

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Discussion Starter #18 (Edited)
Thank you all for all the suggestions.

When we were talking last night. He admitted he had no idea about our engines, and I don't either really, but I guess he is going based on how easy it is to start. He figured that there was a lot more room in there to play with. His is .049 piston to head, about .012 piston to valve. His pistons were cut to even allow the valve to go down in the piston so not to touch. He figured mine had to be like 100 thousandth with how easy it is to start. This stuff is confusing to me. Hard to believe such a small difference can either be way good, or totally the wrong idea.

His engine builder is comming down here next Wed and wants to see my bike. He'll give me his insight on this to.

In all honesty - I like what Metal has done with the super charger.

I really like the idea of the turbo to.

Oh well, it really doesn't matter when there is no cash to throw at it.

I'm just planning for the future. No sense in going to the races knowing your're going to get your azz handed to you unless the big guys don't show up. BB650 know's who I'm talking about....Young Guns Race Team. Them fuggers are fast as hell.
 

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you need to start getting seriuos about hp to weight.. those built shees are putting over 100hp to the tire and they weigh 300lbs if even that
Sorry, but, no turbo, blower, whatever is going to help vs that unless you get a lighter bike or , a lot more hp...
 

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I just spanked the crew at Newtown Drag Way but it was Bracket racing but came in 1st out of about 70 bike LOL,most of the races around here are Bracket or have bracket racing at the heads up tracks also,so I build to race the races we have.
 
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