Front sprocket blocked - how to remove?

[GabrieleItalia]

Hi guys.
I'm writing from Italy. This morning I’ve tried to change the old front sprocket with new, on my F3S 2018. I've got 29000km on the F3. The only problem that I have is that I can’t get the front sprocket out, because of the rust. We tried with a specific lubrificant, with an extractor tool, and with a “phon” (hot air gun). Have you a different solution?

I'm in a panic and don't know how to fix the situation. We've broken a piece off the front sprocket, a piece of the outer lip. The Spyder is now at my friend's motorcycle repair garage.

Thanks for anyone who can help me and sorry for my English.

 

[SpyderJerry]

What ussualy happens is the pulley will have spline left on the inside of pulley that catches the spline on the shaft. I used a gear puller to get them off. You can possibley hold the shaft still and rotate the pulley to get the groove to line up.

 

[GabrieleItalia]

Thanks for your answer.
You mean that the front sprocket is slipped slightly on the drive shaft?
Because I've checked, but everything is in the right place.
But there is a lot of rust. It seems they have welded together because we can't get them out.
We've applied a lot of power with a gear puller, so much that we broke the side lip of the sprocket.

 

[RICZ]

At the same time you are using the gear puller, apply heat with a propane torch or heat gun to expand the pulley. That should help to loosen its grip on the shaft and loosen the corrosion inside. Don't do it too long and heat the shaft too.
Your English is a lot better than my Italian, even though I have been to your country motorcycling the Alps and Dolomites. Where do you live?

 

[Hypurone]

Try a "penetrant" like Liquid Wrench or similar... Penetrants have the ability to "walk' themselves into the rusted areas that are not reachable... Let this stuff soak overnight. Might want to reapply after 4-6 hours then let sit... You may still need to use heat on it while pulling with the gear puller. A "heat gun" won't have enough BTU to do this type of thing... A SMALL butane torch carefully applied to the PULLEY, NOT the shaft should do it. You want the pulley center to expand not the shaft.... Best of luck!

 

[RICZ]

Agreed on the penetrant. The very best penetrant is home made. It's 50/50 transmission fluid and acetone. I saw a very good video testing every brand of penetrant plus that one and to took far less torque to undo the equally corroded bolts in the test.

hypurone...I mentioned the heat gun in case he doesn't have access to a torch. It's better than nothing.

 

[pauly1]

Buon Giorno! If there is "rust" then there is wear in the splines of the sprocket. The splines on the shaft are narrower than the width of the sprocket: that will result in a narrow web of unworn spline on the very inside of the sprocket that must be aligned with the shaft splines to get it off the shaft. That happened on one of ours.

To facilitate alignment, I removed the retainer bolt, then placed a spacer under the head of the bolt, and screwed the bolt back in place. High torque is not required. Now the bolt head can be used to stabilize the shaft while trying to align the sprocket on the shaft. Looking at the sprocket, the shaft applies power in a CCW direction: the sprocket likely needs to rotate in a CCW direction to align the unworn sprocket splines with the shaft. If the sprocket is frozen on the shaft, then a penetrant should aid in its release. The retainer bolt head can be held with a box-end wrench and the sprocket can then be manipulated to try for the alignment. If the sprocket splines are not aligned, a gear puller will not be able to remove the sprocket.

I would be very cautious applying a propane/butane torch to heat the sprocket: there is a rubber seal on the shaft and lots of electronics around the sprocket that could be affected.

I posted this a while back: https://www.spyderlovers.com/forums...ve-Sprocket-(that-has-significant-wear)/page2

 

[Piratezz]

I am going to give a radical solution, since you already have a new sprocket, if all the above advice do not take care of the job, my solution would be to try and saw the sprocket open just about to the splines on the shaft, then support the sprocket on a block of wood, and split it open, with an old screwdriver and a hammer, be sure to stut the sprocket, else all energy will go into the motormounts...and will definetely cause damage.

This is a last resort solution, if all elese fails, no guarantee

 

[GabrieleItalia]

thank you so much guys for your valuable advice. we tried with different extractors but it didn't move in the slightest. we also applied heat to the front sprocket but not excessively, for fear of creating problems At the electronics. in the end, we chose to drill holes in the front half of the sprocket and we managed to remove it. it's like you've cut it. tomorrow we will proceed with the second half, which is incredibly still attached to the crankshaft. they seem welded. never seen anything like it. again, thanks to everyone for the support.

 

[GabrieleItalia]

I’m doing this maintenance because this summer I will do over 4000km around the Alps.
Last summer I made a tour of Sud Tyrol, an Alps’s region here in Italy, with Stelvio Pass, Rombo Pass, Pordoi Pass etc…
But Italy is beautiful, especially on a bike.
I live in the middle, near Florence

 

[RICZ]

I’m doing this maintenance because this summer I will do over 4000km around the Alps.
Last summer I made a tour of Sud Tyrol, an Alps’s region here in Italy, with Stelvio Pass, Rombo Pass, Pordoi Pass etc…
But Italy is beautiful, especially on a bike.
I live in the middle, near Florence

My wife and I rode in northern Italy and found the people, the roads, the scenery and the foods to be beyond wonderful. I could go back in a heartbeat.
Good luck with the remainder of your project. I can not stress enough that checking the front pulley SHOULD BE a regular mantenance item. Better to do it too much than too little. Be sure to use a Moly Paste to lube the splines and I do not have a problem with reusing the bolt.

 

[Peteoz]

thank you so much guys for your valuable advice. we tried with different extractors but it didn't move in the slightest. we also applied heat to the front sprocket but not excessively, for fear of creating problems At the electronics. in the end, we chose to drill holes in the front half of the sprocket and we managed to remove it. it's like you've cut it. tomorrow we will proceed with the second half, which is incredibly still attached to the crankshaft. they seem welded. never seen anything like it. again, thanks to everyone for the support.

Gabrielle, can you post a photo? It is often better to see a photo of the offending item, even though you have it off, to see just what might have caused it to “weld”. Are you aware of the correct paste to use when reinstalling to reduce the chances of stripping reoccurring?

Pete

 

[GabrieleItalia]

Yes guys. I’ve already bought the moly paste for the crankshaft and the loctite 243 medium strength for the new bolt that I will torque to 125nm. As soon as I have finished the job, I will post the photos of the conditions in which the crankshaft is. For now I'm waiting to finish the job, just to be superstitious
Again guys, thanks for your support!
Hope to finish tomorrow.

 

[Gwolf]

If you need to get real serious with the heat expansion of the pulley, then pack dry ice on the end if the shaft for about an hour, then do the heat applied to the pulley only, no heat on the shaft, while pulling. That will give you about double the normal heat expansion you get with just applying heat. We used this method to install or remove shrink fit items. Mostly very large stuff in a mining machine shop where I worked for many years. You can slip a pulley or impeller on a shaft that is several thousandths larger than the hole in the pulley using both heat and cold.

 

[BMac920]

This may help: https://www.spyderlovers.com/forums...nt-Drive-Sprocket-(that-has-significant-wear)


good luck...Regards


Sorry I see you have resolved, IGNORE

 

[dondje]

If you need to get real serious with the heat expansion of the pulley, then pack dry ice on the end if the shaft for about an hour, then do the heat applied to the pulley only, no heat on the shaft, while pulling. That will give you about double the normal heat expansion you get with just applying heat. We used this method to install or remove shrink fit items. Mostly very large stuff in a mining machine shop where I worked for many years. You can slip a pulley or impeller on a shaft that is several thousandths larger than the hole in the pulley using both heat and cold.

Gwolf...

My dad taught me that one over 50yrs ago. He was a shipboard motor electrician/machinist in the navy and later as a navy contractor. Good for getting bearing races out of cases also. There can be some big motors and supporting drive systems on ships.

Regards,

Don

 

[GabrieleItalia]

https://imageshack.com/i/pohaRwOip

https://imageshack.com/i/poiicb8mp

https://imageshack.com/i/pmKTbdHAp

https://imageshack.com/i/pmBe82rup

https://imageshack.com/i/popSyv35j

Ready for the horror pics!
This job was a pain.
At the end, all is gone fine. Now, I've cleaned all the zone.
This morning I'll check up and test the spyder. I've waited over the night and afternoon to make hard the medium loctite that I've applied on the bolt. Hope I don't do any damage. So stay tuned.

 

[Freddy]

Well done GI. Reliability sure ain't Spyder's strong point but folks keep buying them. And as long as they continue to do so at the current rate BRP ain't gunna get their collective knots in a ball over a 'wear item' like the drive pulley. History has shown that to be the case. :banghead:

 

[BMac920]

.......

Ready for the horror pics!
This job was a pain.
At the end, all is gone fine. Now, I've cleaned all the zone.
This morning I'll check up and test the spyder. I've waited over the night and afternoon to make hard the medium loctite that I've applied on the bolt. Hope I don't do any damage. So stay tuned.

Those images represent a lot of work, frustration and winning determination! Bravo and thanks for the photos! Regards.

 

[Piratezz]

The photo's show a horrible job, but I think you sorted it well, and as far as reliabilty goes... The spyder is a complex machine, but with proper maintenance, it is a wonderfull machine...
I've had mine for a bit over two yrs now, and other than an oil change and brake pads that wore out within 8000 km's, I've done 16.5000 km's with a big smile on my face