Crank Question

[Rhein]

Hey guys, newb to this board, not a newb when it comes to others though like vwvortex. Anyway I tried search and read through posts to no avail.

I just got a bike again after a 5 year hiatus.

My question is that I am doing a top end rebuild (been 6 years since my last one and I have forgotten a lot) :bang: and I got some rust on my crank.

I am really worried about something being damaged down there. Is there any way to safely remove surface rust? The crank still turns great no signs of rust on the crankshaft bearings. I just don't want to screw anything up and get advice from the pros here. Thanks :cool:

 

[Rhein]

OK so I just used WD40, It worked great and got rid of all rust. Do you know if this will damage anything? Feels good?

Thanks

 

[2strokerfun]

It's going to depend on where the rust was and how much. Obviously, if its in the bearings, you might have serious problems. What concerns me is that there isn't a whole lot of crank showing down in the case with the lower end assembled, except for the throws. WD-40 in and of itself is not dangerous, but where exactly was your rust and how much? On the flywheel end of the crank, outside the cases is usually not a problem.

 

[Rhein]

It's going to depend on where the rust was and how much. Obviously, if its in the bearings, you might have serious problems. What concerns me is that there isn't a whole lot of crank showing down in the case with the lower end assembled, except for the throws. WD-40 in and of itself is not dangerous, but where exactly was your rust and how much? On the flywheel end of the crank, outside the cases is usually not a problem.

thanks for the reply :cool:

There was very minor surface rust. I don't know how to describe what parts (not on rod) it was on so forgive me but it was on the surface of the two round throws(?), only the part visible with the cylinder off besides rod. I hope that I described it right.

I was still able to easily crank it (with the rust visible) by hand and felt no disturbance and heard no noise. I removed all visible rust and I checked with a flood light down there and there was no rust left.

OK I should have mentioned this earlier but this is how the rust got there. The original owner said he got a tiny bit of coolant down there taking the cylinder off. He turned it to show me that there was no rust and there wasn't. I bought it brought it home and I cranked it by hand and the coolant became visible. There was no rust anywhere but when I used a towel to wipe it as it turned it then became rusted a day later where I used the towel.

I am assuming that it is because I got the coolant off it became unprotected from ambient air and rusted where I wiped it?

So I guess it isn't as bad as I thought?

Sorry for the blabbing