Snowmobile Fanatics banner

1 - 9 of 9 Posts

·
Registered
Joined
·
52 Posts
Discussion Starter #1
Long story short, I bought a 96 Ultra SP with heavy front end cosmetic damage last year from a salvage yard for $385.00. After another $90 in esentials to make it run (exhaust header, engine strap, nosecone, belly pan etc. it was alive and ran great. Anyway, fast-forward to today. I bought a 93 Storm chassis for parts ($190) I needed the track, hood, belly pan so now I have an Ultra w/ Storm looks.

The question is this, since I changed my track out and have the gears out anyway, I was wondering about mixing the Ultra and Storm gears for more performance. The Ultra gears are 21/35 and the Strom is 23/37. Is it worth it to go 21/37 and what will that give me for a ratio? Or should I just leave it be at 21/35. The rest of the sled is stock except for a primary with a red spring...(that is another story).
 

·
Registered
Joined
·
187 Posts
Ok, the 21/35 is a ratio of 1.66. The 23/37 is a ratio of 1.61. At 8k rpm, this is only a 4 mph difference. With a stock sled, this might bog down on the low end, and not allow the clutches to shift out fully. If you were to pipe the ultra or do some sort of power mods, i'd say leave the stock gearing in. If you have any questions, feel free to ask. -Polaris Doc
 

·
Registered
Joined
·
52 Posts
Discussion Starter #3
What if I were to do a 21/37? I am guessing that would take the bog out.
Piping would be the next mod I would do.
 

·
Registered
Joined
·
187 Posts
21/37 will give you 1.76:1 ratio to be used with a 66 pitch chain, BUT is not recommended. A 20/35 will give you a 1.75 ratio, and can be used with the 64 pitch chain that you have with the 21/35. The lower ratio will help with bog, but will have to be clutched accordingly to prevent excessive rpm. Best bet is to fix the clutching, and leave the gearing alone. My 96 ultra sp was piped with slp pipes and it absolutely rocked. best mod you can do to an ultra. Can be a bit finicky, but if you know what you're doing, its not that bad. Keep in mind reliability goes on the shelf with the stock parts, but this is a pretty solid engine to pipe. Hope it workes out. -Polaris Doc
 

·
Registered
Joined
·
52 Posts
Discussion Starter #5
Great response Polaris Doc. I did not think about the chain pitch. Thanks a ton!
 

·
Registered
Joined
·
187 Posts
If you'd like i can email you a gearing chart which is pretty self explanitory. It can show you what to use, not recommended, and what can be used safely but n/r. -Polaris Doc
 

·
Registered
Joined
·
1,420 Posts
pross63, if you end up piping that Ultra I know of a few sets for sale throughout the US. I'm always willing to help a fellow WI ultra guy!
 

·
Registered
Joined
·
52 Posts
Discussion Starter #8
Thanks wiguy05. I may be interested in some info on the pipes. I have a really banged up expansion chamber and was thinking of going all out this season with pipes. My biggest problem right now is I need to find a new throttle cable assembly.
 
1 - 9 of 9 Posts
Top