Have a 99 4x4 Scrambler 400 - ready to start playing with the 2-stroke engine, but probably not ready to spend all the money some of you seem to have on new heads, carbs, etc. Sounds like a "basic" place to start is the pipe and air filter - Keep reading good things about UNI versus the K&N, so that sounds easy.

Unfortunately, I ride out of a friends' place so noise is a consideration. If I get a pipe, but put on either the stock muffler or a silencer, doesn't the silencer reduce the benefit of the pipe? Also, I'd appreciate info on how easy/expensive changing the reed is.

From a former car mechanic who doesn't know diddley about 2-strokes.......
-Thanks for whatever advice you guys wanna share
-Dave

 

You might want to wait and save your money until you can purchase RCR's(Rick Ritter Racing) Stage One kit. Come's with air box mod, main jet, silencer and pipe. It's the best $325 you will ever spend. I know a lot of people that will agree with me on this one. But even if you decide to just do a air box mod, remember you may have to rejet.

 

someone on here has a hsp exterminater kit and he says only a few souped up banshees have beat him. the thing is its $1400 but well worth it you will gain about 30 more hp

 

Yup, the RCR Stage One seems to be the concensus for most bang for the buck. RCR
The very cheapest noticeable improvement is probably to change to the white or green primary spring.

 

Totally agree with you sport. I'd say the next thing after that would be a clutch kit ($180+?). I checked on the V-force reeds and spacer. Reeds=$129.00 and spacer=$28. By the way Davein, it's relatively easy t change out the reeds. Do yourself a favor and spend your forst $30 on a service manual. you won't regret it.

 

If you are concerned with noise, do not buy any RCR pipes. Rick told me that his pipes cannot be used with the stock silencer. I ended up buying a HPD trail pipe from him with an RCR silencer. My intentions were to switch back to my stock muffler for hunting season. So, I started out with Rick's silencer. When hunting season came, I put my stock muffler on. I actually seemed to have more low end power this way. It was also alot quieter. Just to be sure, I switched back to the RCR silencer for awhile. It made great top end power but my low end was gone. For about 9 months now, I've been running my HPD trail pipe with the Polaris muffler. No problems whatsoever and my neighbors like me alot more.

To start out modding, I did air filter, then reeds, then pipe and clutch kit and head shave, then cylinder porting and Wiseco piston, and last was reed spacer. About the only thing I didn't notice power gains from was the air filter. The most gains were noticed when I did the porting.

 

I carry both RcR pipes and Hpd pipes . Hpd pipes will mount to RcR silencers , Hpd silencers , and factory silencers . RcR pipes must use RcR silencers .

Bear in mind though , RcR pipes have an internal stinger built in that quiets the exhaust tone before it gets to the muffler .

LOUDEST

HPD pipe with RcR silencer or any straight through silencer

RcR pipe and silencer

Hpd pipe and Hpd MTQ

Hpd Pipe and factory muffler

QUIETEST

 

Thanks to all for the advice.
I suppose I overdid the "stingy" reference - don't mind spending a few hundred, just not up for $1400...

So, todays questions from someone who has worked extensively on cars but not on 2-stroke engines are:
1) The service manual is a great suggestion - especially one that references accessing the Reed, etc. Any suggestions on which one to get?
2) On the Polaris Scrambler 400, is the clutch adjustable on its own, or do you have to buy a clutch kit to make changes....
3) If I try the pipe, and I start out with the stock muffler and not a silencer, does the stock muffler pretty much eliminate the gain in HP from the pipe, or do you still get most of the power increase?

Thanks to all
Dave

 

The Polaris CVT's are very tuneable. You can change springs, weights, or helix's to your liking, or just by a pre-assembled kit. As for the service manual, I would highly reccommend the factory Polaris service manual. It's worth its weight in gold. I have always felt that the cheaper off brand manuals just don't cover the inportant parts. You can get the manual from your dealer or online at Pure Polaris

 

I used to use the HPD pipe with stock silencer and it sounded awsome. The stock silencer also gave me more bottom end without much loss of top end. The stock silencer might not look as cool as the aftermarket ones but it saves your ears. I now have the AAEN top end pipe with the stock silencer and it sounds even better than the HPD pipe. The HPD pipe had a lout tingy sound that drove me nuts. The AAEN pipe Still has the same sound but not nearly as loud. I have had alot of comments on how cool mine sounds. You should just go for the big one and go for the HPD race mod. Thats ALL you will ever need. 80+ hp. VROOOOOM!!!