How to a weld the pulley on the shaft?

[Chooch]

I have considerable experience welding pulleys to transaxles, fans to shafts, etc. Bevel shaft and bore of pulley as Roadiemort suggested. Also, fit pulley over shaft and shim between the shaft and pulley using shim stock or wire to ensure that the pulley stays centered on the shaft. Then it will be necessary to seat the pulley all the way to ensure it doesn’t wobble when it is turning. Then pack the back of the pulley and shaft with wet rags to protect the bearing and seal from heat and sparks. Protect the threads on the end of the shaft. Tack weld, pour water on the assembly to prevent heat from traveling up the shaft, spin the shaft to make sure it turns true. If it doesn’t run out or wobble tack weld the opposite side. If it wobbles try to tap it back into position. Go slow. It’s easier to grind a tack than a deep weld. The pulley has to turn true with no runout! Good luck.

[roadiemort]

Get a pro to weld it and follow the steps above, if you're not a welder.

[Brad_G]

I wasn't going to mention this as it's not how I'd want to repair this (I'm of the opinion that a new shaft and pulley is the way I'd want it repaired) but if we're looking at alternatives....

On another forum I'm on this issue came up but the shaft and pulley weren't nearly as damaged as yours. In his case it's worked so far. But I don' think he puts a lot of miles on. And with yours having significantly more damage I'm not sure if you'd see the same results. I might consider it for a short term repair with a different pulley and this compound.

https://www.starbikeforums.com/threads/what-did-you-do-to-your-bike-today.2227/post-1107059

[Chooch]

I agree that a new shaft and pulley is the preferred method of repair. That is how I would repair my own.

[Brad_G]

Chooch, I agree completely. I'd only entertain this band-aid repair if it were late in the riding season and I only planned to get a few hundred more miles in before winter. At which time I'd plan to tear down and replace parts.

[davej]

You can also weld it tight and be done with it. If it ever needs to come out for some reason cut the weld and replace the shaft. It's a 5 minute job

[MidnightRide]

You mean it's a five minute job to weld it now, right?

[JoeX]

You can also weld it tight and be done with it. If it ever needs to come out for some reason cut the weld and replace the shaft. It's a 5 minute job

I can't weld ... I have to look for someone. Before I do it some questions:


1. Welding the pulley on the shaft not on the nut, I think
2. Which kind of welding.... electrical or with gas?
3. Is it possible to weld the shaft without deforming it?
4. Is it stable to weld only the outside (hope you understand)
5. Put the nut and the washer again on the shaft? But maybe after welding there is not more enough space?

[davej]

I would install pulley and nut. Weld the inner nut to the center of the shaft then weld the outer part of the nut to the pulley. Then cool it as quickly as possible, in fact I would cool it after welding the nut to the shaft. Wire weld. (Mig) The worse that can happen is you will have to replace that shaft and you need to do that now. Nothing to lose.

[Chooch]

Weld the pulley to the shaft. Install the nut to keep the pulley on the shaft in case the weld fails. Manual arc welding. I suggest DC reverse polarity and 7018 rod. The shaft will not be deformed. Welding just the outside is not ideal and you are correct to be concerned about the stability. Both sides of the pulley should be welded for a permanent repair but is impossible to do. If I were to do this I would fit the pulley to the shaft, then rotate the pulley clockwise until it contacted the shaft tightly. This would allow the shaft to drive the pulley just like it has been doing since you bought it. The weld would prevent the pulley from rotating back and forth on the shaft. Also the shaft would support the pulley across the entire length of the bore.

[davej]

The only problem I see with welding the pulley to the shaft is the time it takes to do that and the heat transfer thru the shaft to the rubber seal. That is why I recommended what I did above. there would be less heating on the shaft and then cool the shaft on the backside of the pulley to keep the seal intact. I guess a few quick tack welds on the shaft to pulley with the 7018 rod would possibly be OK but I would personally go with the nut to shaft then nut to pulley. But that is just my thoughts.

[Chooch]

I agree that heat transfer through the shaft is a problem. That is why I prefer stick welding in this situation. The heat is concentrated and if cooled immediately it won’t have time to migrate up the shaft especially with the pulley acting as a heat sink and absorbing a lot of the heat.

[Mr. Miyagi]

I think that we can safely change the title on this post to "How to weld your drive pulley to your shaft". Just making light, no harm intended, I would be saving up some money to buy the parts I needed because I think the riding time is short before the winter comes. But I am guess on how many months of riding is left this year in your country.

[JoeX]

Good point .... I changed the title.

[KFallsRider]

ChoochIf your welding the pulley to the shaft with the nut & washer on it how do you get access to the hub to weld it ?
If you weld the pulley to the shaft without the nut & washer (each spline) ..the slag and the weld itself would need to be flush enough to get the washer & nut on and tight. Then you can add a couple welds to the end of the shaft and nut..? Jus curious as the weld is the only thing holding it on ..do you omit the nut and washer..the OP is asking that if I read it correctly

[KFallsRider]

Are you getting this JoeX ?

Start looking for a qualified / certified Welder

[Chooch]

Hiring a pro welder may or may not save you money compared to the cost of new (or good used) parts. I think we were referring to a do it yourself project.

[KFallsRider]

Sux to be him..Yamaha EU doesn’t distribute R* parts there..

[JoeX]

KFallsRider asked "Are you getting this JoeX ?"

I hope so .... tomorrow I will make a new video and explain what I understood.

[roadiemort]

https://www.worldtimeserver.com/current_time_in_DE.aspx

[roadiemort]

KFallsRider asked "Are you getting this JoeX ?"

I hope so .... tomorrow I will make a new video and explain what I understood.

What did you decide?

[Duke]

If your planning on welding, then I fully agree with Dave.
With the nut torqued tight, it will keep the shaft tight against the inner races on the bearings.
I, myself would not weld my pulley, unless it was to get me home.

[davej]

Duke is is in Germany and I believe they is a parts availability there

[roadiemort]

Yes Duke, the way you and Dave suggest will surely only get you home, if the shaft wasn't so mangled I would agree. I think the OP is considering epoxy again, Lol.

[brianmac]

do it once do it right, both are toast from the pics .

[brianmac]

https://www.partzilla.com/product/yamaha/4WM-1755A-00-00?ref=6d62aa377c07aed0a5c9ce62286368c8a05c97a6

[roadiemort]

Hello! Has the JB Weld cured yet? lol.

[KFallsRider]

Bump