Barn of Parts New Driveshaft Solution

[HABS 1]

I have reservations about fitting the bearing tight on the shaft.

If your tunnel and caliper housing do not hold the shaft ‘true’ - the caliper will wobble and the side of the tunnel flex.

I had this experience when I green loctighted the bearing to the shaft.

These sleds are built so flimsy compared to the apex and nytros with the cast bulkheads that were machined to hold all 4 drive bearings

Ms

this is why im hopin the new bop design will enable float,while still holding inner race, fingers crossed

 

[Turboflash]

Instead of pinning the ahaft and notching the bearing, they should spray weld and machine the shaft for proper fit and send back the shaft with puller included for future removal. The puller is literally a plate with 3 bolts. This would likely be cheaper than what they are doing right now and would t need attention to the shaft itself ever again. Simply replace the bearing when needed.

If you're talking a press fit, then besides a puller to get it off, a special press tool is needed to install it. If you're talking just a better/closer fit but still a "slip" fit, then the press-on tool won't be needed. My sled has that bearing pressed on for last 3 years. Had shaft spray welded to build up, then ground on centers to get to a .0003-.0005" press fit with a new (better) bearing. No BOP wedge required. When I checked it about a month ago during my maintenance cycle, it was perfect, no evidence of movement between bearing and shaft. Just re-greased bearing and put it back together. If anyone is interested, I can give you pictures of my special press tool.

 

[KnappAttack]

I have reservations about fitting the bearing tight on the shaft.

If your tunnel and caliper housing do not hold the shaft ‘true’ - the caliper will wobble and the side of the tunnel flex.

I had this experience when I green loctighted the bearing to the shaft.

These sleds are built so flimsy compared to the apex and nytros with the cast bulkheads that were machined to hold all 4 drive bearings

Ms

If the bearing is tight on a shaft that is not bent it can NOT wobble or flex and will always run true.

For the guys running this small pin, just put in a 1/4 set screw and red loctite it in place and grind a larger slot in the bearing. The slot does not need machined, it can be ground in using a die grinder or dremel tool as well. A 1/4” set screw will last much longer than that rinky dink little pin. Think outside the box!

Keep in mind if there is any slip fit at all, there will always be wear on the shaft, bearing and pin because even though it’s not rotating, it is flexing and moving a small amount. This is why the wedge on a new shaft is a much better option, or a nut tightened down on the bearing race to hold tight.

 

[justinator]

I have reservations about fitting the bearing tight on the shaft.

If your tunnel and caliper housing do not hold the shaft ‘true’ - the caliper will wobble and the side of the tunnel flex.

I had this experience when I green loctighted the bearing to the shaft.

These sleds are built so flimsy compared to the apex and nytros with the cast bulkheads that were machined to hold all 4 drive bearings

Ms

Just like knapp said, if the bearing fits on the shaft tight its impossible for it to wobble because it will be on there straight and stay straight.

 

[Sevey]

If the bearing is tight on a shaft that is not bent it can NOT wobble or flex and will always run true.

For the guys running this small pin, just put in a 1/4 set screw and red loctite it in place and grind a larger slot in the bearing. The slot does not need machined, it can be ground in using a die grinder or dremel tool as well. A 1/4” set screw will last much longer than that rinky dink little pin. Think outside the box!

Keep in mind if there is any slip fit at all, there will always be wear on the shaft, bearing and pin because even though it’s not rotating, it is flexing and moving a small amount. This is why the wedge on a new shaft is a much better option, or a nut tightened down on the bearing race to hold tight.

That is assuming the tunnel is ’true’ - when the crossshaft is off, and the calliper housing off - that tunnel is as flimsy as a tissue. Whether i have done something, or they come out of the factory slightly different - who knows. I am convinced the clown engineers want some kind of flex in the design because something else might break if it was held tight. In short. - i agree with you - but everything has to be perfect. Based on what i have seen on my sled -something is off.

I have spoke to the guys that did the pinning and they are looking into a larger pin. The design works, its just not robust. Even the wedge wont hold things for long. All that rust in the pic is a good thing. If it was moving there would be no rust. Lol. That pin is some kind of hardened steel so its not some soft roll pin. Off topic - i had issues with my Nytro‘s drive shaft not running true and spinning on the bearing. It was likely due to a hard it and the drive shaft warped. As an experiment i drill a hole into the shaft to screw the ‘set screw’ of the bearing into. It had it sheared off in no time. A set screw is not likely hard enough steel - even if they are stainless.
Ms

 

[HABS 1]

im thinkin if all else fails ill put some key stock threw shaft, only stickin out 1 side, tac weld on inside of shaft, simple, then machine slot completely threw inner race to accept, will hold it and let the tunnel or whatever do what it wants, only hiccup im seein is thickness of inner race to machine slot

 

[KnappAttack]

That is assuming the tunnel is ’true’ - when the crossshaft is off, and the calliper housing off - that tunnel is as flimsy as a tissue. Whether i have done something, or they come out of the factory slightly different - who knows. I am convinced the clown engineers want some kind of flex in the design because something else might break if it was held tight. In short. - i agree with you - but everything has to be perfect. Based on what i have seen on my sled -something is off.

I have spoke to the guys that did the pinning and they are looking into a larger pin. The design works, its just not robust. Even the wedge wont hold things for long. All that rust in the pic is a good thing. If it was moving there would be no rust. Lol. That pin is some kind of hardened steel so its not some soft roll pin. Off topic - i had issues with my Nytro‘s drive shaft not running true and spinning on the bearing. It was likely due to a hard it and the drive shaft warped. As an experiment i drill a hole into the shaft to screw the ‘set screw’ of the bearing into. It had it sheared off in no time. A set screw is not likely hard enough steel - even if they are stainless.
Ms

You have to understand, even if the tunnel or housing is "off" it will absolutly not wobble. It can ONLY wobble when the bearing is crooked on the shaft or the shaft is bent. Under no other circumstance can the tunnel or housing wobble.

The engineers did not design flex into the chassis or bearing. Nothing else can "break" if the bearing was held tight on the shaft. Ski-Doo does it right with a press fit on the bearing to shaft, and a snug fit in the housing that will not rotate, but it can take more effort to get it apart as the housing needs a bit of effort to get off the bearing.

The Wedge works well to hold things tight when tightened enough and normalized when tightened down so it doesn't cock the bearing on the shaft. The problem (wobble) comes when the bearing is not normalized straight on the shaft. It wont wobble with a good shaft and tightened in stages to nominalize on the shaft and not sit crooked.

Stainless set screws are not hard. You'd be better of with a regular steel set screw. The pin being used for this shaft anti-rotation mod reminds me of a piston ring locating pin, its just way too small. If you insist on using a pin or dowel like that, the old two-stokes used much larger anti-spin dowels in all the crankshaft bearings.

 

[STAIN]

Curious how do u use a microwave on a steel object ?

 

[sidewinder 2018]

I imagine when the sled is cold things are pretty stiff. As a general rule I usually roll the track on a stand and take it easy for the first few kms to warm things up- shocks, bearings etc

And still that pin is hitting the bearing pretty hard
Ms

Sevy,the pin reconditioning repair would have increased durability with the increased diameter from the current 1/8” pin to 3/16” or .250”that would require opening up the slot also.Should be interesting if Franks offers this as an option going foward

 

[justinator]

Well isnt that awesome!

 

[STAIN]

Well isnt that awesome!

I have actually done this when rebuilding a rear end for a truck, works slick.

 

[Sevey]

Sevy,the pin reconditioning repair would have increased durability with the increased diameter from the current 1/8” pin to 3/16” or .250”that would require opening up the slot also.Should be interesting if Franks offers this as an option going foward

I sensed they hadnt received much feedback from people because very few have pulled their sleds apart since installing their pinned shaft and slotted bearing.

Kam seemed interested and was going to speak with their machine shop. I too will be interested to see what they do.
MS

 

[sidewinder 2018]

I sensed they hadnt received much feedback from people because very few have pulled their sleds apart since installing their pinned shaft and slotted bearing.

Kam seemed interested and was going to speak with their machine shop. I too will be interested to see what they do.
MS

What Will be interesting also will the new repair coming out from B.O.P. to address this issue.I believe he will be deleting the tunnel side debris bracket/and seal,and ring.Then ,the installation of a custom compression fitting that picks up the tapered inner race(edge) of this bearing ,is pressed into the caliper housing, Then on to shaft.as one assy.Time will tell.

 

[Sevey]

im thinkin if all else fails ill put some key stock threw shaft, only stickin out 1 side, tac weld on inside of shaft, simple, then machine slot completely threw inner race to accept, will hold it and let the tunnel or whatever do what it wants, only hiccup im seein is thickness of inner race to machine slot

Keep us posted on what you decide to do.
Would love to try a 'key way' as a fix but do not have the kind of tools required and certainly dont have the experience to machine it.

MS

 

[Sevey]

You have to understand, even if the tunnel or housing is "off" it will absolutly not wobble. It can ONLY wobble when the bearing is crooked on the shaft or the shaft is bent. Under no other circumstance can the tunnel or housing wobble.

The engineers did not design flex into the chassis or bearing. Nothing else can "break" if the bearing was held tight on the shaft. Ski-Doo does it right with a press fit on the bearing to shaft, and a snug fit in the housing that will not rotate, but it can take more effort to get it apart as the housing needs a bit of effort to get off the bearing.

The Wedge works well to hold things tight when tightened enough and normalized when tightened down so it doesn't cock the bearing on the shaft. The problem (wobble) comes when the bearing is not normalized straight on the shaft. It wont wobble with a good shaft and tightened in stages to nominalize on the shaft and not sit crooked.

Stainless set screws are not hard. You'd be better of with a regular steel set screw. The pin being used for this shaft anti-rotation mod reminds me of a piston ring locating pin, its just way too small. If you insist on using a pin or dowel like that, the old two-stokes used much larger anti-spin dowels in all the crankshaft bearings.

Based on your comments I can only conclude that when trying green loctite (a few seasons ago) on the shaft, that it began to set - before i got everything tightened up (3 - 10mm bolts inside the tunnel). Because things were way out of line. Since then i have been wary.

I totally agree the pin is too feeble. At this point i would like to see something 3/16 or 1/4 dia as the pin.

MS