splitting the crank

Twangled your powervalve grommit in your woodruff key? ask someone how to fix it here
mj43
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Post by mj43 »

Ok - assume gear box is out :)

Turn engine over and undo the bolt holding the water pipe.
Turn engine backover.
Clutch side undo the clutch/engine cover. On teh water pump cover only undo the lower rear bolt - that one holds the engine cover on. The other two just hold the water pump cover to the engine cover.
With all the bolts undone carefully remove the cover - it has to come off the water pipe, and the kickstart shaft.
With the cover off remove the kickstart shaft - I pull the pin that the spring is attached to out. Be careful there is a washer behind the kickstart which tends to stick to the cases.
Spin the motor round - remove the flywheel need a puller for that. three allen bolts remove generator. Three cross heads hold the timing cover remove those and the timing cover.
Turn the engine upsidedown.
Balance weight cover remove the 8mm head bolts. Remove the tapered cross head at the front of the cover (KR-1S only). Undo the 4 x 12mm head bolts in a cross pattern a bit at a time just to loosen then completely.
Lift off the balance weight cover - don't loose the two locating pins (haven't mentioned those before there are two on the gear selector cover - in fact two on all covers).
Lift out the balance weight - dont loose the rubber bit at the end. Put somewhere safe. (when putting it back it has two punch marks on teh gear these align with teh same two marks on teh crank gear). Don't loose the two half circle steel locating clips.
Next undo all teh 8mm head bolts holding the crankcase halves together.
Next the 8 x 12mm head bolts - half a turn at a time work around the numbers in reverse order. Repeat twice then undo all teh way.
Split the cases :) remove teh crank, and locating hal circle thing, and teh gear box bearing and its half circle thing.

Thats it :)
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Garry
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Post by Garry »

all that in 15 mins :shock:

my heads spinning :)
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mj43
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Post by mj43 »

One day when I am bored I will video it :)
Then we will see if it can be done in 15mins, I made that number up but reckon I could just about do it [-(
mgtkr1
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Post by mgtkr1 »

once you have done it a few times it becomes very easy, same order without really thinking about it. i bet mj could actually do it in around 15-20mins. the gearbox is very easy, a little awekward to get in but not to bad. a shame khi didnt make more ratio's to give it a purepose to be used more often. there is the kit gears, others close ratios aswell kicking about but it would of been nice to have had a proper selection like the tz and rs gp bikes. oh, getting the balance shaft in with pipes on/engine in situ takes an octopus or houdini. but that said its do-able like everything el;se on the best engined 250 thats why i favour it over arguably better handling/more up to date 250's. so easy to work on yet the engine has some beutifully engineered work on it. check out the oil gallerys in the gearbox. why the tolerances were all over the shot is beyond me but suspect it wasnt actually as common as it seemed at the time, the wonders of m/cycle press?
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nate
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Post by nate »

15 minutes is going some.... Then again, if you know exactly what your doing and don't have to worry about locktite and some tosser cocking up the heads on screws... ](*,)

Anyway... after the minor flap this afternoon (Thanks MJ... it was the posi drive screws)... I finally achieved this... :mrgreen: :mrgreen: :mrgreen:

Image

I started at 9.30 this morning and took this pic at about 5.15 this afternoon.. I was in the pub for 5.45 though :mrgreen: :mrgreen: :mrgreen:
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the-elf
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Post by the-elf »

Have to agree with MJ. Once you've done it a few times its only a quick 15 min job. provided that those cross head screws don't strip.
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