SOLUTION for Worn W-arm Shaft

[garserio]

Has anyone pulled out their Proactive suspension yet for pre-season maintenance? I always pull my rear skid before each season to inspect for worn bushings, damage, shock rebuilds, etc.

Last year, I rode 2,000 miles (half hard miles, half trail miles) on my Vector and here is what I found... The front aluminum shaft that secures the W-Arm to the tunnel had significant wear on the ends where the plastic bushings ride. One of the bushings had worn through and the other was paper thin.

(By the way, I grease my sled before every ride whcih for me is an average of 150 miles.)

The aluminum shaft was worn about 0.050" and out of round in the bushing area. The aluminum is simply not robust enough. The obvious solution is to make a new steel shaft, but then you suffer the weight gain.

My solution was to turn the ends of the shaft down by 0.050" x 1.5" long. I then press fit a steel sleeve onto the step. Then, after the press fit, I turned the sleeve to final shaft diameter of 21.75mm. Now I have a light shaft with hard end surfaces for the bushings to ride.

A new shaft runs $30 from Yammie and you will be replacing them every 2,000 miles with risk to the W-Arm. My solution should last forever if I keep up on the $3 bushings every season.

See picture...

Have fun, Greg

 

[scott boddie]

i have the same problem thanks for the idea 2987 miles my shaft is junk but i ride very hard trails

 

[Flipper]

You should check all the bushings in your rear skid and front A arms. After 8000km of riding last season, many of the plastic bushings in my sled needed replacing.

 

[Handy]

Did the same repair to mine in the spring. I had one bearing that the flange broke off of when I changed slidders in Feb. last season and it slid into the center of the shaft. The other end was only worn 0.010" but I sleeved both ends to be sure. I didn't post this repair because I thought every one would know about it as in the 70's & 80's it was comon practice after first year on any brand sled.

 

[garserio]

Hey Handy... Thanks for the history of this problem.

I thought I was being all "inventive" with the repair!

Well, I guess you can forgive me... In 1975 I was in diapers and in the 80's I was watching cartoons!

In 1987 I rode my first Jetski and it wasn't until 1993 before I grabbed my first handful of sled throttle...

In 1998 I rolled my 600sx for the first time with only 200 miles on the odometer which pretty much proved to me that snomobiling is not jetskiing... Falling off is a BAD thing on a sled!

:ORC

Today I ride a lot smarter...

 

[BETHEVIPER]

if you shim the bushings tight the grease doesnt pound out to leave the bushing dry. when it is dry it will wear either the bushing or the shaft. you have only fixed one part of this problem. if you didnt use stainless you have another problem. the ends will get pitted with rust and tear the bushing even faster. this is what happens to the lower bushings in the warm and the front shock. steel collars get rusty, then tear the hell out of the bushings(they are loose to start with)

shim all bushings tight , install bearings in the front shock, machine a groove in the upper shaft for Oring and all will be fine. even better would be if you did your trick with all of these and used stainless.

 

[garserio]

if you shim the bushings tight the grease doesnt pound out to leave the bushing dry. when it is dry it will wear either the bushing or the shaft. you have only fixed one part of this problem. if you didnt use stainless you have another problem. the ends will get pitted with rust and tear the bushing even faster. this is what happens to the lower bushings in the warm and the front shock. steel collars get rusty, then tear the hell out of the bushings(they are loose to start with)

shim all bushings tight , install bearings in the front shock, machine a groove in the upper shaft for Oring and all will be fine. even better would be if you did your trick with all of these and used stainless.

I did go with stainless... you other suggestions definitely have merit, but I probably won't go that far. I expect to have to go through bushings every year, so my main concern was to make sure that the shaft wasn't wearing every year as well. Since there are no seals to "blow-out", I feel that overgreasing is a good thing to ensure grease gets all the way to the end of the shaft and into the bushing clearance. A little oozing grease never hurt anyone...

 

[pistons]

My 1996 V-Max XT has needle bearings instead of bushings, straight from Yamaha. They had it right then, wonder why not now? $$$$$$

 

[LazyBastard]

There is a problem with needle bearings; they need more maintenance. Very frequent greasing. They are subject to ice and sand. Its also cheaper to put in plastic bushings.

 

[Handy]

There is a problem with needle bearings; they need more maintenance. Very frequent greasing. They are subject to ice and sand. Its also cheaper to put in plastic bushings.

Needle bearings do not perform well on a soft shaft. For needle bearings to opperate properly the shaft would have to be hardened to 60 Rc. or higher. Since we have aluminium to save weight plastic works much better. stainless steel is also a soft metal unless you go to the 400 series and then you would have heat treat and grind the sleeve before you could run a needle bearing on it.