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99’ m900 Crank plug/budget rebuild

6373 Views 72 Replies 4 Participants Last post by  Czakky
My ratty, crappy, wonderful, little sh*tbox has backed out the crank plug…. sigh.
I’m going to fix it.

Looks like I need an alternator cover puller, a uh crank plug, and a quart of 3-bond. I don’t see any gaskets on Stein Dinse’s awesome website for the left side.

Am I missing something?

I’m sure there will be a few “while I’m there” things but I like to have as much on hand as possible.

thanks for any help
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No you do not want the end of the crank deformed, yes it takes a lot of pressure.

protect it as best you can the part is tough and will withstand a bit of force. we used to load the gear up and throw a towel over the puller, leave it over night and find the puller and gear on the floor in the morning.
I gave it a bit of pressure and measured a small amount of deformation. I didn’t measure it before so I can’t say if I caused it. Good idea leaving it in tension overnight!

I use gear pullers a fair amount at my job. It’s amazing how little force it takes to deform even a 2”+ solid shaft. Of course these are usually not high grade steel shafts.
They are only as strong as they need be. The factory probably never expected owners would be doing to them what we do.
i use an old guzzi copper washer, not sure where it comes from now, to protect the end of the crank. put something soft, but not too soft, between the puller and crank. i also leave the nut on, loosened a couple of threads to contain the flying mess.
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Ha! I had a thick copper washer from an old Honda S90 rebuild I’m using with the nut a few threads up the shaft.

I gently heated the gear, applied pressure, worked on another project, tightened, went to bed, woke up with hope. Still attached, tightened, staying hopeful….
Reading up on other folks doing this job it looks like I underestimated this one by a lot. Seems like my weeny 3t puller is not man enough for the job. I will have to borrow one from work me thinks…
i use something like this. one of the feet has been ground to fit in behind the gear nicely, and possibly welded as well for strength.

we used a factory tool at a training course in '98 to remove a gear. the big bang was the tool breaking. gear 1, tool 0.
Last night I set the biggest puller I could get under the gear and tightened as hard as I dare. I woke up this morning to check it out to find the towel it was under slumped over! Something happened!
Tool Wood Engineering Machine Auto part

it’s on now!
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There is a hydraulic puller like Belter uses on eBay I’m going to grab….
you need a flat end too, not a tapered one like that. the end of the crank needs to stay as it was.
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Will do. FWIW I had a heavy washer on the crankshaft end
Is there a special socket required for the con rod bolts?
My 10 or 11mm didn’t fit, I couldn’t find anything online….
should be a 10mm 12 point.
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Yeah, I feel like an idiot….
  • Haha
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Big end shells are showing about perfect for clearance all around. I ended up bending one of the locating pins on removal. Not sure if I’ll try and replace it or not.

Ive got about $140 in parts from Ducati and about $250 from a bearing supplier so far…

I still need to decide if I’m going to replace the sprag gear or not. There are $40 on eBay, most Duc shops want around $100. Duc shops are pretty important to these bikes though…

Still waiting on the hydraulic puller too…
i wouldn't put any non genuine shit anywhere near a starter clutch.
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I’m not sure if there is anything to see here. I’ll probably just let it ride. It’s not a “ cases split” proposition to replace the starter clutch. Though much easier at this point.
Food Recipe Ingredient Bivalve Banana

Hand Automotive tire Watch Finger Bicycle part
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Uhhh... you seem to be missing some starter clutch there.
The bottom race(?) steel(?) part stayed attached to the flywheel when it pulled out.
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