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KX60 Lower End Rebuild

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Original post got lost in the transfer.

Doing a rebuild on the lower end. The lower connecting rod went. I have disassembled the engine. There doesn't appear to be any other damage due to the bearing going bad. I was going to buy a complete rebuild kit with the flywheel, gaskets and bearings. May check a local machine/engine shop to see what it would cost to rebuild the existing crank. I did purchase the flywheel puller. Used a gear puller to split the cases. A borrowed electric impact wrench made the clutch and flywheel nut removal pretty easy.

Questions:

When installing the crank assy back into the right side case it requires a special jig to insure the proper clearance between the case half and the crank same goes when installing the left case half. What is the thickness of the jig or what should my clearance be? Seems like I could make the jig myself pretty easily if I knew the thickness.

All the other bearings in the case appear good. Should I still replace while I have it apart?

I'm guessing I'll likely be better off with the rebuild kit. If I do replace all bearings and seals I'm thinking the cost of those individualy plus the cost of the crank rebuild will be more than the complete kit.

Thanks for any input.

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I'm doing the exact same thing to my kids 2001 kx 60. I ordered the wiseco rebuild kit off e bay, still waiting for it to come in. I don't know anything about the jig though, I'll have to look into it. If I come across anything I will let you know on this thread or hopefully someone else can help us out. Thanks for starting this. Good luck.

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Same Kit I was looking at. If you get it post what it includes. I've read some are not "complete". Also hear that it's a good idea to check the crank for alignment, but that's just off the net so...

In the clymer Manual they show a jig which appears to be a flat piece of steel about 3" wide with a cut slot in the middle, kind of like a fork with only two prongs. The jig is slid through the opening on the cases where the cylinder is mounted, between the wall of the case and the flywheel with the slot fitting around the crank shaft. As the crank is pressed into the case the jig prevents you from over inserting the crank and provides the necessary clearance between the case wall and the face of the crank wheel.

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When I do bottom ends I heat the bearings/cases and freeze the crank....you can assemble by hand and center the crank with feeler guages between the cases.

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I put the seals in the cases, set them in the sun (on hot summer day) or in the oven, surface temp only needs to be around 100-120 degrees. Then drop the cool bearings in the cases, let them heat up. Put the crank in the freezer for 1/2hr. Now the trick is to get it together quickly. Then fill the space between the counter weights with something solid (punch handle) then center the crank between the cases, I put the nuts on the ends and use a piece of wood and light hammer DON"T HIT IT HARD just light taps. I'm not sure of a spec I just make the gag = on both sides. I've also used the same method but put the bearings on the crank first, then slide cases together. Your gona have to oil the heck out of the crank and bearings as the warm back up as they will condisate.

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Hey Bryan h, I got my bottom end rebuild kit today. It includes the crankshaft assembly( with rod) and all the bearings, gaskets and seals needed(I hope!). It's a Wiseco kit that I ordered off eBay for about $180.00 including shipping(Canadian). Might be cheaper for you. Time to get at it!

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Fired it up today. It's in my basement so I can't run it for too long. So far so good.

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Glen77,

In the basement...? That would have flown like a brick at my place, or it would have flown towards my head.

Waiting until next week to order parts. I think I may have been thinking the whole clearance thing wrong. As a test I refit the old crank into the case using the hot bearing /cold crank and it easily slipped into place flush against the bearing. Rotated smoothly. So is there no measurement between the crankcase counter weight "wheel" and the face of the case?? The crankshaft "wheel" appears to have a slight lip that would butt against the bearing providing the necessary clearance.

Did you also do your topend at the same time?

Did you replace your alignment dowel sleeves? Mine are pretty stuck, didn't want to force the issue.

Thanks

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I have a work shop down there that has a couple doors between it and the rest of the house so I get away with it.

The top end was new last year. Everything seemed to fit together very well. I put the bearings and the crank in the freezer for a while so that helped. I didn't touch the dowels.

I didn't worry about the gap between the crank and the case. It looks equal on both sides and everything moved nicely.

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Got a few of the part orders in this week.

Wiseco Complete Bottom End Rebuild Kit - I'd call it more of a complete crank rebuild kit. Comes with crank, both bearings (open ball KOYO brand). Two O-rings - water pump and shift shaft, Three gaskets - Water Pump elbow gasket, Clutch cover gasket, flywheel gasket. Six seals - two crank, kick starter, shift, drive, water pump. Also the piston rist bearing. $112 plus shipping

Also got an Athena Top End Gasket Kit - Comes with Two exhaust O-rings. Two gaskets - head and base. $18 plus shipping

I mention this for others reference as I ordered a water pump seal and the exhaust o-rings seperately not thinking that would come in these kits.

Edited by bryan_h

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I got everything back together. Heating the case and cooling the bearings helped a bit but still needed to press them. Bike started fine, let it run till it warmed up a couple of times. Will do a few more until we actually go out with it. I mixed my oil at 20:1 to insure adequate oil. Will switch back to 32:1 once I get a few break in cycles. Did take a slow spin to insure the trans was working and it too seemed fine. Drained oil and coolant after I was done. Time will tell but for now all is good.

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Cool! We have to wait to ride ours yet, just got a foot of snow over the weekend. I cooled and heated my parts too and still needed to persuade them a bit.

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I know this is being brought back from the dead.. but I'm hoping these guys are still here... can you help me get parts list I need and steps to donit on my own? Did you guys just buy the complete kit? Or did you guys buy new bearings and redo the original crank... I got this bike free for my son and I'm wanting to get this done... just not familiar with bikes and need walked through the process... I know I can do it.

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