I have a 99 , 600 Grizzly, with 25" ITP Titan tires. I like the speed and handling I get with this combination, but I could still use a little more power, especially in the bottom end. This bike is all stock and in mint condition. Any ideas on where to start would be appriciated.

 

Clutch kit to gaun some bottom end with the different tires and a pipe for the engine[img]i/expressions/face-icon-small-wink.gif[/img]

 

my son is in the process of modding his grizz ported and polished headz oversiz bore big high compression and exaust but with all the high flows and sizes hes having trouble feeding it now cant get enough gas to it he need a bigger carb i think its a whole new ball game for set up , a bit painfull

 

You can get the 673 big bore kit since the 600 (595cc) has the same motor as the XT600 had for years. There is also the 635cc bore kit, the 595 has been around for years. Yamaha just shoved one in a ATV in 1998 to freak people out and start the big bore war we have now. Link to 635 kit
https://www.slipstreamperformance.co...ducts_id=22750

 

Might just need bigger jets all around, not a whole new carb.

 

i think he is close to 780 cc with a 200 jet and its not running right yet for jeting with four turns out on the mixture. he wants to be able to keep up or beat an 800 bombi i think the isue now is that the needle hole is smaller than the jet so he may try running without the jet in the bowl,the bowl on the thing is tiny compered to a sled carb the same size ,and there is a huge veriety of jets available for sled carbs!

 

Hellboy, maybe call Mickey Dunlap's "four stroke tech".
Sure will beat guessing like these other fellas...(and I think he needs a bigger carb too).

 

Now THAT'S pushing an air cooled engine to the max.