I have just installed a Hotseat pipe and clutch kit on my 00 500 Scrambler. Yes there is some improvement but not what I tought. I also added a K&N filter. I am going to jet it up now but getting at the carb is a chore. Before I do any suggestions would be great. My dealer says stock jetting is 155. Does anyone have one of these pipes on there Scrambler? What carb mods did you do?

 

My dealer put mine on. i think the stock jet is 140 but im positive. after i got enuf money i hot rid of the hotseat and got the hpd and there is a big differnce.

 

Changing the main jet is a little time consuming, but its not that hard. The stock jet is 155, after adding a pipe and K&N, 160 should be about right. If you don't want to have to do the job again, put a 165 in and punch a few big holes in your airbox lid. If you have any interest in a Dynojet kit, I'd put it in at the same time as the main jet.

 

Kevin,
What is the story with a dyno jet. Where are the gains.

 

Throttle response seemed to improve some on mine, but not enough to justify the cost. For some reason the main jets that come with the kit are 155 and smaller so even if you have the kit you still have to buy new jets to go bigger.

 

I think the dynojet kits use a different numbering system than the stock jets. If you take a look at the Honda fourm this topic comes up all the time on the 400ex jetting. Also I'm at 4000 ft, 85 degrees, and run my 00 500 Scrambler with a K/N filter and use a 158 main jet and the plug is perfect.

 

I don't pretend to know it all about jetting, but if Dynojet has their own numbering system as compared to Polaris', then that is one of the most boneheaded things I have ever heard of.

 

I put a 160 main in today took it out and tested it and there was no improvement. I ran it before the pipe after the pipe and now after jetting and there no improvments what so ever on the radar, after jetting and very little from stock. I ran it three times at three different lengths, big bucks for little gains. Top speed is only 57 miles hour.

 

That's just the way it is with 4-strokes. The only thing I have done that gave a major noticeable improvement was a new primary spring and weights along with a roller clutch. Unlike the 2-strokes, building the 500 is a gradual process.

 

If you want a better gain go with a hpd pipe. Because i had the hotseat pipe and it snapped so i went with something differt and it helped alot even no it was runnin very lean it still ran better than it did with the hsp. Sorry to hear that you fell for the hotseat to.