Jackshaft Bearings

[Big_bill]

New to Yamis last year. Searched this forum for info on Jackshaft and drive shaft bearings and did not find any. My question is how many miles before I should replace. My last sled was a 2000 Polaris 600 Touring that I put on over 29000 miles. It had grease fittings on both top and botom shafts and never had to replace. I do not want to break down while out riding, so any info would be greatly appreciated.

 

[steiner]

Depends if they have dried out or have rust in them.
I'm changing mine at 10k miles. I also pop off the seals and grease the bearing atleast once a year. Probably don't need to but I will for peace of mind.

 

[4strokeluvr111]

IMO - 5-6000 miles tops. Run Yamaha (Toyo) bearings only.

 

[J1635]

theres no set life on bearings, if the last guy didnt take care of them even for 1 season they can be trash.

personally i opened up my chaincase and changed them all since i was doing other work anyway, half looked good the other half i wouldn't bet on.

some people run them dry others with grease its all personal preference. if your opening them to look then slap a bit of high temp marine grade grease in, make sure theres no play yada yada etc. none of them have any grease nipples your used to, its all hand packing. and if you dont wanna break down then id say change them if you have any doubts

also only run OEM, you need to be aware if trying to match them up somewhere else that one of the bearing housings is tapered on one side so personally i think its faster just to order it from a yam dealer for a little extra $$

 

[4strokeluvr111]

On the clutch side jackshaft bearing, make sure you install it in the right direction. It's slightly tapered and will only go in one way.

 

[Roger]

I had many Polaris' before my first Yamaha. The grease fittings were nice, and common sense actually to have them.
There is no set life to a bearing. If you let it get rusty, change it. If it wears out, change it. I've had lots of sleds with 10000miles on them, and besides the wheels in the track, I never changed a bearing, except one, in my traded 2007 Yamaha RS Venture, with no grease fittings.
It was the jack-shaft bearing at the secondary clutch. I was fiddling around, repacking bearings with no fittings, when I noticed I could move the secondary up and down by hand. We all know that you shouldn't be able to move it around. After some searching on this site, found a Sweedish guy that changed this bearing without taking the sled apart to do so. That bearing is tapered, and is quite the job to change. I made a tool, like the Sweedish guy did, used a heat gun to heat up the aluminum around the bearing, and out she came. No need to take apart the whole frigging chaincase!!!

Hope this helps, and good luck, if yours' is worn.

 

[Koenig]

'Roger', what tool is this? Is there a link to building it, or a pic? Curiosity has me thinking....

 

[Roger]

'Roger', what tool is this? Is there a link to building it, or a pic? Curiosity has me thinking....

It's a home made tool. I live just south of Ottawa, if you're interested in seeing it. I have that tapered bearing as well, which I could sell to you, since I don't have that sled anymore anyway.
Try this link, it's where I saw it in the first place. Look through the whole thing, it's there somewhere.

http://www.ty4stroke.com/threads/driveshaft-jackshaft-bearing-regrease-step-by-step.52677/page-4

 

[Koenig]

Roger, sent you a PM last week... never heard back???

 

[Roger]

I'll see if I get a chance over the next few days to take a picture and post it.

 

[Roger]

The first picture shows the end of the tool ground down to fit between the shaft and the bearing once you have removed the wedge/nut part of the bearing. The other small piece is a shim made to hold the tool tight, from the opposite side of the shaft, once you have the tool in place.

This is the actual pull hammer tool I made with scrap metal laying around the barn.

This is the placement of the tool, and shim. Pretend that the piece of plastic pipe is the jackshaft. You have already loosened and completely backed off the nut behind the bearing. I used a long punch and small hammer. The nut is actually pulling in a tapered piece toward the nut. So, you have to actually remove the wedge toward yourself. You can't get at the back of the wedge to knock it out, so, since the bearing is already euchred, take a punch, and gently tap the bearing right beside the wedge. The wedge spacer will start to work itself towards you. Once the spacer has been removed, there is quite a bit of slop in the jackshaft. Insert the tool, so it hooks to the back of the bearing. Place the other shim opposite the tool. The tighter the fit here the better, because you have to pull the weight toward yourself to yank the bearing out. Take a heat gun and heat the aluminum around the bearing until the aluminum is good and warm. If you don't heat it, it won't work, as the bearing is pressed into the aluminum. The inside of the bearing is tapered. The wide part near you, the small end, toward the chaincase. Have the new bearing ready to install right away, if you wish, while the aluminum is warm. I kept the new bearing frozen, thus a touch smaller. Have a piece of pipe handy that is slightly smaller than the larger part of the bearing. Use the pipe to drive the new bearing in all the way.
I believe that making the tool is quicker than taking the chaincase apart to get the jackshaft out, to change the bearing.

 

[Roger]

Here's a link to the hard way, the way the dealer would do it, hours of work, for nothing!

http://www.totallyamaha.com/snowmobiles/aaTECH/Jackshaftreplace/Jackshaftchange.htm

 

[Woodrow]

New to Yamis last year. Searched this forum for info on Jackshaft and drive shaft bearings and did not find any. My question is how many miles before I should replace. My last sled was a 2000 Polaris 600 Touring that I put on over 29000 miles. It had grease fittings on both top and botom shafts and never had to replace. I do not want to break down while out riding, so any info would be greatly appreciated.

You need to grease them at least every 2000 miles. If you do, you will never have to change them. I have a way to easily remove the bearing, Cant attach photos as they are too big, but i can email them to you if you want. For re-grease this guy has it nailed down. Both bearing he shows I also do every year
http://www.ty4stroke.com/threads/jackshaft-and-driveshaft-bearing-re-grease.113610/#post-1008694