Beefin Up A 1 Lunger [Archive] - Snowmobile World : Your #1 Snowmobile Forum

: Beefin Up A 1 Lunger


dubie
02-02-2005, 01:47 PM
Is there anything I can do to my little 92 Star Lite 1 lunger to give it a little more power? Certain kind of clutch, or carb mods, boring the cylinder etc...
Just curious

NewfieBullet
02-02-2005, 02:03 PM
Not alot you can do, aside from being sure everything is adjusted proprely. Well, there's probably lots you could do, but why spend the money?
A couple of freebies would be to shave the head a little, and clean up your ports. You'd have to be brave to start shaving the head without knowing what you're doing, and if you're that brave you might as well raise your exhaust port 1mm or so.

flylake
02-02-2005, 02:43 PM
shaving the heads on some of these older sleds is pretty easy. All you need is a surface plate (thick piece of glass or flat smoothe steel) and various grits of wet sand paper, preferably glue backed.

Measure the current head thickness. Glue a sheet of 120 grit paper on the surface plate. Using a circular motion and the paper wet with water, keep the head flat on the plate and remove between .005-.015 of material. Change to 200 grit and clean up the surface. You don't want to have a polished surface. The lines created by the 120 grit paper help the gasket seal. Sometimes I'll make a few passes with 80 grit paper before the 200 to put a nice swirl pattern in the mating surfaces.

How much you remove depends on the type of head, how much compression you want, and the type of gasket used. For example, the old air cooled Cats with the copper shim gaskets, you can remove up to .035, but then you need to run racing gass all the time.

In an ideal situation, you'd cc the head to calculate compression ratio with different amounts removed before you begin.

If you don't have that ability, a good place to start is to remove about .010 and go up one grade in the fuel you are using. Some gasket companies have oversized gaskets available to reduce compression if you go too far, but I wouldn't count on that. Best to start small.

Increased compression will not result in that big a power gain. And it won't add much to the "feel" of the sled either. The best thing you can do to make your sled "feel" stronger is play with the gear ratios, clutch weights and carb jetting. For example, increasing the primary weight will lower the RPM at which your sled launches, but reduce top end RPM. Reducing the weight will make your sled launch harder, but at higher RPM.

There are so many things you can do (my machinest calls it "juggling snakes"), but the real question is should you do anything. Keep in mind what the sled was originally designed for, how you ride, and the cost involved vs the expected results.

You may find you are better off selling this sled and buying a more modern machine. Used sled prices are cheap with mid 90s 500s and 600s selling well below $1000. Given the lack of snow this year and upcoming warm weather you may be able to find a great deal for under $500.

dubie
02-02-2005, 03:46 PM
We sure have no lack of snow here this year. We have at least 38" of accumulated snow on the ground. This sled is a great sled that I'll keep for the kids, they are 8 and 6 now, so in a few years they will be riding on their own and following mom and dad. I just figured if there was a way to produce a bit more power out of it, it would be fun to play with right now.

Thansk for the info guys

northern700sks
02-02-2005, 09:37 PM
Maybe you should put the engine out of Shawna's 58 in the sled!

Funny how paths cross!

dubie
02-03-2005, 04:36 PM
Originally posted by northern700sks@Feb 2 2005, 09:59 PM
Maybe you should put the engine out of Shawna's 58 in the sled!

Funny how paths cross!
397667



Chris?? is that you?? or someone else??

flylake
02-03-2005, 08:48 PM
Originally posted by dubie@Feb 2 2005, 05:08 PM
We sure have no lack of snow here this year. We have at least 38" of accumulated snow on the ground. This sled is a great sled that I'll keep for the kids, they are 8 and 6 now, so in a few years they will be riding on their own and following mom and dad. I just figured if there was a way to produce a bit more power out of it, it would be fun to play with right now.

Thansk for the info guys
397504


Let them ride it now. Heck, my kids started riding younger than that.

You guys are spoiled :tongue: We had snow, but it melted. The trails are all down to the dirt now. This has been a lousy year for snow in NH.

northern700sks
02-04-2005, 12:33 PM
northern700sks on snowmobileworld.com

northerngmc on 67-72chevytrucks.com/stovebolt.com

Those 250's are one of the hardest starting snowmobiles I have ever pulled.

Didn't the 58 come with a 250, cubic inches of course!