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My first inclination would be to say don't, but you want to so your going to do it anyway.

Put the bearings in the freezer, heat the case half, once warm drop the bearing in, by the way this is after you've installed the seals, and don't heat around the seal area or you'll damage the seals. OK, you have the crank bearings/seals installed, now heat up a metal slug (solid steel about the size of the inner bearing race) to about 400-450 degrees, once hot place it on the inner bearing race and let sit for about 5 minutes, pull off the slug and insert the crank through the bearing (clutch side first) it should slide right in. OK, lay the right case on its side and install all the gears into the right case. heat the slug again and place on the left side case bearing race, while it is expanding the bearing, apply case sealer on the right side case, I like yamabond 4 myself. bearing is expanded, slide the left side case onto the crankshaft, should slide right on, (rod at bottom dead center while doing this). ideally you will use a special tool to support the crank so you don't knock it out of alignment, then you will tighten the case bolts. If it is tight you can tap on the end of the crank provided you have your special tool in place, otherwise your going to cause misalignment and you might as well order another wiesco crank cause you'll need it. This is an easy operation IF, you have the right tools, don't let anybody touch the ends of your crank without support or you'll cause misalignment.

Bottom line I would at least have somebody show me the first time, its not that difficult, but, if you get it wrong the bike will vibrate and won't last, then you'll be peeved at wiesco, when in fact it was the installation technique.
 

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My first inclination would be to say don't, but you want to so your going to do it anyway.

Put the bearings in the freezer, heat the case half, once warm drop the bearing in, by the way this is after you've installed the seals, and don't heat around the seal area or you'll damage the seals. OK, you have the crank bearings/seals installed, now heat up a metal slug (solid steel about the size of the inner bearing race) to about 400-450 degrees, once hot place it on the inner bearing race and let sit for about 5 minutes, pull off the slug and insert the crank through the bearing (clutch side first) it should slide right in. OK, lay the right case on its side and install all the gears into the right case. heat the slug again and place on the left side case bearing race, while it is expanding the bearing, apply case sealer on the right side case, I like yamabond 4 myself. bearing is expanded, slide the left side case onto the crankshaft, should slide right on, (rod at bottom dead center while doing this). ideally you will use a special tool to support the crank so you don't knock it out of alignment, then you will tighten the case bolts. If it is tight you can tap on the end of the crank provided you have your special tool in place, otherwise your going to cause misalignment and you might as well order another wiesco crank cause you'll need it. This is an easy operation IF, you have the right tools, don't let anybody touch the ends of your crank without support or you'll cause misalignment.

Bottom line I would at least have somebody show me the first time, its not that difficult, but, if you get it wrong the bike will vibrate and won't last, then you'll be peeved at wiesco, when in fact it was the installation technique.
+1
I don't have all the correct tools and that is why I don't install them in the Kawi's myself, just like our customers bring their Harley's to us becuase they don't have all of the correct tools.

You can do this and the information just given is very good advice I must say!
The most important tool is the crankshaft jig, becuase more than likely you will need to tap the crank one way or the other to get it centered up once the case halves are bolted together. Without the jig you do run a very good chance of pinching the flywheels together when you try tapping the crank to center alignment.

Another tip is to put the crank the freezer for a while, but this will only help when doing the first (right hand) side. I have heard people say that this is hard on the rod bearing due to condensation, but that just isn't true, after all if you oil the bearing first, condensation won't be a problem. I have rebuilt several Honda mini's without a crank jig, but the seals go in afterwards and so you can heat the main bearing with a porpane torch if need be to align the crank for center. Can't do this on the little Kawi due to the seals going in first.

Hope this helps you some , Dave
 

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Tree Magnet
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Discussion Starter #4
(rod at bottom dead center while doing this)
How will I know it's at BDC? Is there a mark? I have a service manual, but it doesn't say.

Put the bearings in the freezer, heat the case half, once warm drop the bearing in, by the way this is after you've installed the seals,
So I can put in the oil seals, THEN heat it (say in an oven) without damaging the seals? Then once the case is warm/hot, drop the bearings in...right?

I'm starting to think we may have to miss this weeend's race and take this to a real mechanic.... :(
 

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How will I know it's at BDC? Is there a mark? I have a service manual, but it doesn't say.

So I can put in the oil seals, THEN heat it (say in an oven) without damaging the seals? Then once the case is warm/hot, drop the bearings in...right?

I'm starting to think we may have to miss this weeend's race and take this to a real mechanic.... :(
You don't need to worry about BDC. Don't put the seals in the case and then the case in the oven or the seals will be crap. I use a propane hand torch to heat the bearings outer race in the case after installing the seals. Keep the heat away from the seal and it won't take long for the case to heat up. Then remove the bearing from the freezer and the bearing can be tapped in with a 2X4 and hammer with the case sitting on a piece of plywood. I use my press to pop in the bearings. If you have a large C clamp that can be used with a socket or the old crank bearings to press the new bearings in the case halves. I wouldn't suggest the 2X4 method. I have a link for engine rebuilding without special tools at home on my laptop and will post it later on today.
 

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FPMXer, post that link when you get a chance "engine rebuilding without special tools" i'm going to be doing some rebuilding pretty soon and need to learn more about this stuff. I didn't realize that the crank alignment could be a problem when putting the cases back together after the crank is already installed on one side of the case...
 

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Having just done this myself for the first time ...
Take Your Time! if it dont feel right stop and figure out what went wrong.
Dont force anything.

Thats all I have
 

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Tree Magnet
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Discussion Starter #9
Yeah. I've decided not to rush, since it's the off season. The boys can share the other bike for a week or two while I do this right. I just remembered/rediscovered that the shifter lever is welded to the shift shaft, so I'll have to order a new shaft and cut the lever off anyway.
 

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I was OK with this guys procedure right up until he said to tap the crankshaft into the bearing, BIG NO NO, only tap if you have the special to to support the crank while installing it, otherwise you run the risk of misalignment. Of course the choice is yours, and you may not misalign it. I've dine piles of cranks and wouldn't think of tapping the crank with out support. An 85 turns high rpm's a little alignment issue will be noticeable at the higher revs. I've spent time truing 85 cranks to near perfect, there is a difference in the way they run. True is smooth and fast.
 

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Tree Magnet
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Discussion Starter #11
do you have any specs on the crankshaft jig to support the crank should tapping become necessary?
 

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I was OK with this guys procedure right up until he said to tap the crankshaft into the bearing, BIG NO NO, only tap if you have the special to to support the crank while installing it, otherwise you run the risk of misalignment. Of course the choice is yours, and you may not misalign it. I've dine piles of cranks and wouldn't think of tapping the crank with out support. An 85 turns high rpm's a little alignment issue will be noticeable at the higher revs. I've spent time truing 85 cranks to near perfect, there is a difference in the way they run. True is smooth and fast.
I agree with you on that as I won't tap on it either. THe freezing and heat method works very well to draw them into each other.
 

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Tree Magnet
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Discussion Starter #15
thanks. I noticed that there is some squeeze out of some gray material between the halves now. Does this sound like factory, or should I suspect this bottom end has been replaced before?
 

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I was OK with this guys procedure right up until he said to tap the crankshaft into the bearing, BIG NO NO, only tap if you have the special to to support the crank while installing it, otherwise you run the risk of misalignment. Of course the choice is yours, and you may not misalign it. I've dine piles of cranks and wouldn't think of tapping the crank with out support. An 85 turns high rpm's a little alignment issue will be noticeable at the higher revs. I've spent time truing 85 cranks to near perfect, there is a difference in the way they run. True is smooth and fast.
+1, if you do tap it without support you will misalign the crank, I can tap them in at work and check its within tolerance with a laser alignment jig and straighten them if needs be, and scim any rust off with a laythe.

I replace my whole bottom end (inc crank) min once a year and top end twice a year.
 
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