Jump to content

Crank bearing replacement


kevlarr
 Share

Recommended Posts

 

 
 
 
 

Bike was smoking and was told that bearing seals needed replacing , £200 later and still smoking . Now quoted £240 labour plus  parts for bearings if I take engine out,   I have access to pullers etc

I have never done it but thought this may be an ideal time to learn. I have no time limit, it takes as long as it takes. Thanks for your replies. 

Link to comment
Share on other sites

 
 
1 hour ago, kevlarr said:

Bike was smoking and was told that bearing seals needed replacing , £200 later and still smoking . Now quoted £240 labour plus  parts for bearings if I take engine out,   I have access to pullers etc

I have never done it but thought this may be an ideal time to learn. I have no time limit, it takes as long as it takes. Thanks for your replies. 

Cant you take it back to the guy that did the initial work and tell him his fix wasn't a fix? 240 with the engine already out is excessive, id be expecting around 150, to a bike mechanic its maximum a 3 hr job

Edited by faussy
Link to comment
Share on other sites

 

Well if you really feel the need to do it, it`s a good time of year to waste some time. Once you do it you feel confident to fix about anything in the future. First off leave the motor completely assembled in the frame. This will give you more leverage to get everything apart. Do the flywheel and stator first. Then everything off from the clutch side. The hardest thing and this point will be primary gear on the crankshaft. Take lots of pics and be organized about it. Do not take off the top end, untill you are ready to remove the motor. Now go watch as many u tube vids as you can. Cut up an old inner tube into 4 small strips to hold the transmission togerther once you have split the motor. It really is not hard to take it apart. Remember to always have the transmission in nuetral while splitting the cases and assembling the cases. What fun you are going to have!

Edited by lineaway
  • Like 2
  • Thanks 1
Link to comment
Share on other sites

 
 

Original diagnosis and quote was for seals and didn’t know it wasn’t them until back together and running. Bearings are a little noisy and that is what they believe may be the problem. Starts and runs fine until riding to sections then smokes excessively 

Thanks for the tips Lineaway

Link to comment
Share on other sites

 
 

 Starts and runs fine until riding to sections then smokes excessively

If the exhaust is full of oil, it may catch fire and smoke excessively when riding to sections.  It will also run funny and have a weird smell, sort of like a rancid barbecue. You could be burning off the oil that built up from the bad seals.  There are some posts on here about cleaning out the exhaust.  Another way is just to run it hard and keep a lot of heat in the exhaust until it burns out.  This could be a long ride at the speed it starts smoking on the way to sections or a nice long hill climb.  Repeat until it stops smoking.     

 

  • Like 2
  • Thanks 1
Link to comment
Share on other sites

 
1 hour ago, b40rt said:

Can someone explain why slightly noisy mains would make it smoke excessively, especially if crank seals have just been replaced ?

 Too much play in the main bearings will cause the seals to leak. But while he is taking it apart I would make sure the seal is new and properly seated.

Edited by lineaway
Link to comment
Share on other sites

 

Mcman56, I did think about oil in exhaust packing as a cause of it still smoking . Do you guys think I should leave alone for a while and see if it calms down. I could change packing first I guess, cheaper option to start with. 

Link to comment
Share on other sites

 

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
  • Create New...