Anyone changed main bearings on a Mototrax?

[tribalbc]

Main bearing on the driver went on my Mototrax kit yesterday. Starting to tear down and it looks to me like I need to split the entire aluminum frame of the track to service the bearings? Have the sprocket off and about to pull the brake rotor but it looks to me like I have to remove the aluminum sides to pull the driver.
Anyone who can offer any tips?

 

[eric82930]

Just remove one side plate. The bearings are the same as timbersled.

 

[tribalbc]

Pretty much the conclusion she's all coming apart.
The damage. Had to limp out about 10kms on the bad bearing.

It was an awesome day until it all went wrong.

 

[tribalbc]

Just remove one side plate. The bearings are the same as timbersled.

So timbersled bearings and seals will fit?

Thanks makes sense on the one side plate.

 

[eric82930]

Timbrsled doesn't have any extra seal. You can run without them or get the seals from mototrax

 

[tribalbc]

Timbrsled doesn't have any extra seal. You can run without them or get the seals from mototrax

Thanks for that. I need a new bearing carrier anyways so seals will come from Mototrax.
Bearings were easy enough to source at local automotive store.

 

[dooman92]

tribalbc, i have replaced both the drive axle bearings on my mototrax. i also had to replace one of the bearing carrier/cups. I dissassebled the entire kit at that time and added grease fittings on the main cross shaft of the motolink. that main shaft has a plastic bushing on each end and in my opinion less surface area than it should have and therefor will wear too quickly without some lube. It is also a good time to relube those pivot points at the front of the motolink. As I recall, there is a needle bearing in there that would benefit from some lube. If you see it as advantagous, the bearing cups can be drilled and tapped to accept a grease fitting. I did that so i could add a little grease between the seal and the bearing ( i think the bearings had a seal on just one side). The grease fitting is positioned at the rear of the carrier/cup and greasable coming in from the rear. Just a thought from an old grease monkey..

 

[tribalbc]

tribalbc, i have replaced both the drive axle bearings on my mototrax. i also had to replace one of the bearing carrier/cups. I dissassebled the entire kit at that time and added grease fittings on the main cross shaft of the motolink. that main shaft has a plastic bushing on each end and in my opinion less surface area than it should have and therefor will wear too quickly without some lube. It is also a good time to relube those pivot points at the front of the motolink. As I recall, there is a needle bearing in there that would benefit from some lube. If you see it as advantagous, the bearing cups can be drilled and tapped to accept a grease fitting. I did that so i could add a little grease between the seal and the bearing ( i think the bearings had a seal on just one side). The grease fitting is positioned at the rear of the carrier/cup and greasable coming in from the rear. Just a thought from an old grease monkey..

Thanks for that.
I need a new carrier on the sprocket side as well. I am replacing bearings all around. Driveshaft, jackshaft and idler wheels. I tore down my suspension linkage last summer and greased everything but I will do again since I have her apart. I do not recall there being a needle bearing in there though...
Good idea on adding a zerk to bearing carriers.
Now that I have done the process though I will probably just swap out bearings once a season. New bearings all around was less than $40.

 

[dooman92]

As i recall, that needle bearing is at the lower end of the smaller arm under the main motolink assembly. Yeah, I replaced all bearings on drive and jack shafts at that time. It was a couple years ago but I think the jack shaft comes with two small bearings in it but mototrax had an update with four bearings. i put four new bearings and seals in the jack shaft. I also drilled and tapped that shaft and added a grease fitting.

fwiw, i am not an advocate for pumping these bearings full of grease. but rather a small amount one or two times a season depending on hours. Pumping ball bearings full of grease causes resistance to the balls rolling as they should. The ball stops rolling and the race slides on the stationary ball because the ball can't push through the grease resulting in abnormal wear. Imo, that is why some greasable ball bearings fail prematurely.

 

[tribalbc]

As i recall, that needle bearing is at the lower end of the smaller arm under the main motolink assembly. Yeah, I replaced all bearings on drive and jack shafts at that time. It was a couple years ago but I think the jack shaft comes with two small bearings in it but mototrax had an update with four bearings. i put four new bearings and seals in the jack shaft. I also drilled and tapped that shaft and added a grease fitting.

fwiw, i am not an advocate for pumping these bearings full of grease. but rather a small amount one or two times a season depending on hours. Pumping ball bearings full of grease causes resistance to the balls rolling as they should. The ball stops rolling and the race slides on the stationary ball because the ball can't push through the grease resulting in abnormal wear. Imo, that is why some greasable ball bearings fail prematurely.

Yeah my jackshaft is 4 bearings.
Now that you mention it again I do remember that needle bearing.
Wrenching too many different machines and old age can mess with your memory I guess, lol.

 

[ProAlpine]

tribalbc and dooman92, my 2019(?) Moto Trax kit has zerk fittings all over the kit. Is this an upgrade from the older ones, or are you describing areas that don't have them that should?

 

[tribalbc]

tribalbc and dooman92, my 2019(?) Moto Trax kit has zerk fittings all over the kit. Is this an upgrade from the older ones, or are you describing areas that don't have them that should?

They were upgraded to zerks everywhere. My kits a 2017.

 

[dooman92]

Proalpine, my kit is a 2017 and did not have any grease fittings stock. So, must be an upgrade on newer units. As i did with my sleds, I installed grease fittings at any pivot point that I could. I have not looked at the newer mototrax kit but, on my 17 I was able to add several grease fittings. Fwiw, On the rearmost cross shaft both in the slide joint (holds the bushing that was aluminum then replace with plastic) and in the joint of the cross shaft with the bushing shaft. The front of the rear arm where it is held in by the cross shaft in the tunnel has a pivot point on a plastic bushing and will take a grease zirk on both sides. The main cross shaft of the motolink (largest diameter shaft) has short plastic bushings on both ends that stabilize the entire suspension. It was easy to put a zirk in the center and when filled with grease pushes out both sides and keeps those too small bushings lubed. You probably have the y-yoke thing that stabilizes the front of the rails. That has small plastic bushings at the lower shock mount point. Mine wore quickly. I made a copper replacement bushing and drilled an 1/8" hole that allowed grease to get to the bushings when pumped full with a needle zirk tool. i will attempt a photo as my descriptions are not great.

 

[dooman92]

 

[ProAlpine]

Thanks dooman92, that's all good info for Moto Trax users.

I purchased mine used and prior maintenance is unknown, so I need to make sure it's all lubed up!

 

[ProAlpine]

I checked my track and I've got zerk fittings in all those spots you mentioned dooman92. I greased them up and should be good for a while.

tribalbc, I did notice that there was not a Zerk fitting anywhere on the drive shaft. I guess you have to disassemble to grease it? I presume they are sealed bearings...

 

[tribalbc]

I checked my track and I've got zerk fittings in all those spots you mentioned dooman92. I greased them up and should be good for a while.

tribalbc, I did notice that there was not a Zerk fitting anywhere on the drive shaft. I guess you have to disassemble to grease it? I presume they are sealed bearings...

There's really not a lot to grease. Two seals and a sealed bearing on each end of the shaft. So just a little grease between the seals and bearing. Bearings sourced yourself are like $10 each so really if you stay on it just replace the bearings once a season and repack seals with grease then. Only downside is you pretty much have to dissamble the whole track so it takes a couple hours.
I was going to do mine last summer but decided I should be good and I learned the hard way. Thought I would have a little more warning but they went from squawk to full destruction in the matter of half an hour.
Missed out on a week of riding here waiting for the new bearing carrier.

 

[ProAlpine]

Copy that.

One other question as it relates to bearing replacement as well as other maintenance items such as chain tension - I can't for the life of me loosen some of the bolts on my kit. Specifically the 3 bolts needed to adjust the primary chain tension. I spoke with a buddy of mine who is a mechanic as well as dirt & snow biker and he said a lot of the bolts that are threaded into aluminum get corroded and seize due to the difference in metals.

Have you run into this problem? Any suggestions? I've been trying an impact driver with a little heat, but with the chain guard on there I can't apply too much heat before that thing starts melting...

Cheers

 

[tribalbc]

Copy that.

One other question as it relates to bearing replacement as well as other maintenance items such as chain tension - I can't for the life of me loosen some of the bolts on my kit. Specifically the 3 bolts needed to adjust the primary chain tension. I spoke with a buddy of mine who is a mechanic as well as dirt & snow biker and he said a lot of the bolts that are threaded into aluminum get corroded and seize due to the difference in metals.

Have you run into this problem? Any suggestions? I've been trying an impact driver with a little heat, but with the chain guard on there I can't apply too much heat before that thing starts melting...

Cheers

Do you mean the 3 bolts that adjust the chain tension and not the bolts on the bulkhead?
I had both my side adjuster bolts break but I managed to thread them out of there housing and cut some custom ready rod and threaded that in there.
The two side tensioners are through holes. You just have the nut on either side to hold it in place. No adjustment is done from these, they strictly hold it in place. All adjustment is done through the center bolt. Back off nut closest to bike and then adjust with bolt head.
If you can't get those side nuts to loosen you could always cut it off and use ready rod like I did.

 

[ProAlpine]

The 3 bulkhead bolts are the ones I can not loosen for the life of me.