Hey guys~
I've had my DS since August and have loved every minute of ride time on it. I'm guessing I have gone about 1300 miles so far, but the top end is feeling noticeably weaker. I just added 22/23" razr's, 4 ply rears and 6 ply front. The 22" razr's only weigh about 3 lbs heavier a piece than the stock kendas(17 vs 14 lbs). When my machine was new, I could easily hit the rev limiter in 5th at about 74 mph. Now, with stock gearing, I could not pull 70 mph on the GPS, and with a 15 tooth front sprocket, I would only hit 67 mph. I don't think I've even been able to hit the limiter in 4th gear since I got the new tires. All these runs were on a frozen lake covered by hard packed snow. I tried some runs with and without the airbox lid installed, but results were no different. I even have the front mini fenders removed to cut down on wind resistance. Here's some things I am thinking could possibly cause the lack of power. 1.I have not changed the jetting at all. I am running the stock settings. 2.I have not changed oil in roughly 20 hours or 300 miles. 3.Cold weather makes everything move a little slower. Anybody have any thoughts about this? The clutch still feels strong and I have not smelt or heard any slipping.

 

Ouch put the other tires on and try those and see wat you get.

 

Thanks hurycne~
I did consider doing that, but then thought it would be a bummer only using 4 new tires for less than a month! It just seems wierd that it pulled so strong with the 20" kenda's, but noticeably weaker with the 22" razrs. The razr's only weigh a total of 6 lbs more and raise the gearing about 3% with the 15 tooth front sprocket. Something just doesn't seem right and I don't know what it is![img]i/expressions/face-icon-small-mad.gif[/img]

 

I don't think your tires are the problem. I have had similar results in cold weather when it takes a long time to warm up the motor. When it is cold it takes a long time before I can push the choke in. The combo of cold air and cold motor makes it run lean, taking off the airbox lid would just make it worse, too much air, not enough gas. If it runs better with the choke on, or halfway on, even though you think the motor is pretty much warmed up, you might try a larger mainjet.
.... I am running a 175 mainjet, K&N, stock airbox, with a HMF slip-on with a self-modified Quiet Core insert, which is somewhat restrictive compared to an open exhaust. The more I think about it, the more I think you need a bigger mainjet, might as well let it breathe with a modded end cap or slip-on since you are headed for the wonderful world of rejetting.
.....Oh, buy the mainjet (s) at your dealer. Save some dough. The DYNOJET needle makes hot and cold spots and I do not like.

 

It could possibly be your jetting. There is big temp change from the summer weather to our good old wisconsin winter temps. I would try to rejet and see if that helps at all.
matty