mod-it
Member
My best guess is gearing and clutching. You're basically running a Mnt Viper. They come with 40-21 gearing (2.14:1 I believe that works out to with 8t drivers). You have really tall gearing, combined with who knows how much weight in the primary. Going from a 9t to an 8t does gear down a sled in itself, but you went to really tall gearing by putting a 25 top gear on trying to get your ratio back to stock...for a short track. You will need lower gearing to pull the load of a 144 vs a 121, or even a 136. I bet there was a ton of performance left on the table when you ran it with that gearing last year. Didn't you say you even put 1200 miles on it with that setup last year and the 144 track? Would it pull 8600 rpm last year with that setup? And, you said it was "screaming" at 70 mph with the 22 top gear...what do you mean by screaming? It was topped out and wouldn't go any faster? My Mnt. Viper has even lower gearing, the stock 40-21, and it will do 85mph on the top end.
It just really seems like to me that the motor can't pull all the load on it, especially when you say it won't even spin the track when you pin it from a stand still.
It just really seems like to me that the motor can't pull all the load on it, especially when you say it won't even spin the track when you pin it from a stand still.
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rubbersidedown
New member
When I say screaming I mean it just seemed to be revving really high for our normal runs. I first had installed the reverse and 136 at the same time. This seemed to be not much of a change. A little less power but I figured longer track eats up horsepower. I switched to 8 tooth so I could run studs with my 1.25 ripsaw. That is when I had the high revving. I new that would happen. I tried to get back close to stock. I am going through my notes and my top is actually a 24, I thought I needed a 25 but it was not easily found used so I went with the 24. Seemed fine. When I went to buy studs the guy I was working with made me a super deal on a 144 ice ripper xt with rail extensions for 165 more than studs backers and double nuts. I then put 936 of the 1200 on a saddlebag trip with my 7 year son as a passenger in front of me so I was not really running flat out most of the time but was ok for power. The next few trail rides is where I started having intermittent tps and powervalve codes and the servo acting up. We tried a few different things and also had the mileage issue so I thought it went hand in hand. That is when I took it to a dealer so I could ride but that did't help much. So I decided to do the used motor with all the components that could be my problem and not be chasing so many different problems. So that hasn't quite been the case. So now I have the carbs all cleaned again. Installed mains from my old carbs that I could read as 156.3. runs fine on stand. I was trying to watch to make sure the powervalves were working but it was hard to tell. They engage when I turn on the key and do some moving as I bring the rpm's up. Seems fine but hard to tell on stand. I can easily switch back the 22 gear but I sometimes want to go more than 85 for top speed. I ride mostly in the 50-75 range and not a lot of off trail. I thought the 144 would carry the weight better and smoother, like my 136 did vrs 121. So I started with stock gearing of 1.73 switched to tooth 24 top 39 bottom 1.83 If I go 22 top 39 bottom 2.00 And yes I have no clue about the clutches I just thought hellclickers would be the way to go.
When you switched to the 8-tooth drivers, did you change or modify the speedo pickup gear to get the correct speed?
rubbersidedown
New member
Yes I ground off two of the teeth on the reluctor wheel as described on this site. Worked great.