i have just put a 54 mm kit in my 90 and it still only goes 37 to 40 are they any way to get it to go any faster? my nephew races it on the fair bracket and still gets killed by a girl on a eton and it killing his man hood lol i have sunk 5000 in it and the old lady is mad so please help

 

What else is done to it?

 

koso intake 28 mm carb boost bottle clutch kits on front drilled clutch on back black spring on back race cdi box i have just put a 130 jet in it but the regular head took lot more gas is that right it took a 140 jet in carb koso muffler i am runing terbo blue racing fuel at 32-1 with beanol carbon fiber reeds super coil i probabley missing some things

 

how fast is 1 of these things go the jug was supose to be ported race 2 from hyper toon

 

I don't mean to be harsh, please don't take it that way. What's you compression? It should be through the roof to run 110 octane race fuel, otherwise you're killing your power. Most people I know of use a mix. Also, I have yet to hear one good thing about that koso pipe. Most people consider it a good boat anchor. After that, the next step would probably be advanced porting. Once it's running good, you can change the gearing to get more top end.

I also highly recommend the WRH aluminum clutch. I don't care how much you drill out, it still weighs twice as much as an aftermarket.

 

thaks i will go down on octane should i just use a 93 or mix it weak with 110 and for the koso it seem to do great and sounds good but what kind o pipe do u recamind do u have any idea on the spead of a dinli

 

I've heard claims as high as 55 mph. Never clocked one. Mine has stock gearing and will easily do 35-40, so I'd say it's possible. I have no need for top speed, I'm just trying to turn paddles.

I have a Hetrick style pipe that was sold under a different name. WRH is also very good and I can't say enough good things about Billy Holt. I've had him on the phone a couple times trying to trouble shoot. The guy is a class act.

 

Tried to go back and read some old posts. My understanding on the Koso is that it needs lighter rollers to work right and that by itself can cost you some top end.

Also, on the fuel I'd look at a 50/50 mix with 87 octane unless your compression is really high.

 

i just got back from work and read some of this it makes since so i will try it thanks alot

 

what kind of atv do u have ????? do u run it on drag