1982 R100RT timing chain
I'm in the process of changing the timing chain and crank sprocket along with the ball bearing in front of the crank sprocket. The manual i have didn't say anything about heating the inner bearing race or the crank sprocket so i just fit my two jaw puller behind the crank sprocket teeth and tried to pull them off. Yes i protected the threads on the end of the crankshaft. Nothing budged so i thought i better slow down before i damage something. I saw that snowbum mentions putting heat to the bearing and sprocket. I don't feel real good about the two jaw puller and really don't like how little material is in contact with the puller behind the sprocket teeth.
Does anyone have the special tools for pulling these items and would you be willing to let me borrow them? My back-up plan is to find a three jaw puller and spark up the torch but only if i absolutely have to.
Heat is what you need. Not a flame though. Use a paint striping heat gun. It will be hotter than a hair dryer, but not hot enough to cause a lot of damage. Heat the gear evenly and thoroughly to where you can not hold on to it without protection, and keep the heat off the shaft as much as possible. The gear will then slip off easily. Installation is the reverse. Get the gear good and hot then slam it home by hand.
1982 R100 cs
I use a DeWalt mechanics' heat gun with digital set point. Some anti-sieze on the shaft (and heat on the outer parts) will help it go back on. If you put it on dry (especially without the proper tool) it will often hang mid-way and then it won't go any farther. You can also then ruin the new bearing trying to remove it. Some anti-sieze also makes the next removal easier. Some people use oil, but I have seen that stick mid-way as well.
Hot means spit-sizzling hot.
When it comes time to install the new parts i will follow the good advise. However, i first need to get the old parts off. I tried heating with a heat gun and it is very difficult not to heat the shaft at the same time. Any heat added to the crank sprocket goes right into the crankshaft. That is why i was thinking torch, it is much faster and the heat doesn't have time to conduct to the shaft.
I may try taking the bearing off separately from the sprocket. Maybe that will help.
A combination of heat and cold? Put a strain on it with whatever puller you have, shoot some compressed air onto the shaft with one hand, and heat on the gear with the other, then with your other hand rap on the end of the puller bolt whilst tightening it all at the same time. The gear should pop off the shaft before the puller breaks. And if it does break, it was the wrong one or the gear was not hot enough. You can do this. I used a Weller heat gun from True Value and it was good enough. If you don't have compressed air, there are options, canned air or something like that.
I have compressed air and a heat gun. I just don't have four hands. I'll have to get help i guess.