Im posting this for a buddy of mine, He has a 99 sport 400L (2 stroke) and he just bought a DG slip-on pipe for it with a K&N air filter. His jetting is not right now, its bogging at low rpms and going up hills. What size jets does he need to get.....and also can he use the same needle or will that have to be replaced also, and also are there any particular reeds that are recommended for his bike (that is I think his has reeds, I know most 2 strokes do at least). Lastily is there any other low cost mods anyone would recommend for his quad, both for handling and power. I think he plans on going with 20" razrs to lower the CG and improve the handling. Any and all help is greatly appreciated, TIA!!

Oops, almost forgot, we are at sea level with usually a fair amount of humidity in the air, thanks.

 

Chances are the it is the pipe causing the trouble DG pipes arent the best thing for a Polaris.You cant get the clutch dialed into one very easy.When you pipe a 2stroke Polaris you need to to clutch to the pipe(2stroke pipes are made to opperate in a certan rpm range and the clutch is what keeps it in the right the rpm range). Have him try lowering the needle a notch and try a 26o main to start out and do a plug check after each change.He might be able to get it where it will be ok but if I were him I would get a pipe and matched clutch kit from either HPD,RCR,Aaen or Hotseat.These guys all specialize in Polaris.

 

I can second that. DG is the WORST pipe for a 2 stroke Polaris. DG does not have clutching to match the pipes and it can actually lose hp. They claim up to a 5percent gain on top end. Well 5 percent of 38hp is 1.9 hp.WOOHOO BIG gain there.NOT!!! Trust us. Alot of us have tried to save a buck and found out the hard way. Now my DG pipe is hanging on my garage looking good because thats all it is good for. He needs to go with a good quality pipe like HPD,AAEN,RCR or Hotseat. These companies deal directly with polaris bikes and get the most hp out of them.Anywhere from 7-9hp. Thats a big gain. DG has NO jetting info and no powerband. Get rid of it and spend $200 on a good pipe.

 

I just want to make sure we are understanding you right. Most of the time a slip on is reffering to 4 stroke unless this is just a silencer. If it is just the silencer and a K&N he may just need to jet up a size or two and lift the jet needle maybe one notch. If it is a whole pipe he needs to get a good pipe and clutch kit combo. Also might try a new plug.

 

Thanks for all replys so far, and yes it is just a silencer that he bought and not a complete system......I hope that clears things up a little, and also its to late as far as telling him to buy another pipe as he has already put the silencer on his bike. I didn't get to go riding today but couple of my friends did say that it felt like it had more snap over the stock pipe even with the jetting not dialed in correctly. Any more info is greatly appreciated, and I will pass on all info and opinions to him that I learn from this post. Thanks again.

 

bump....anyone else with info or suggestions....thanks

 

If the dg silencer fits on the stock pipe then he can still buy an aftermarket pipe and still use the dg silencer. I also use a dg silencer with my pipe. It will fit HPD and AAEN pipes.