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Crankshaft question?

3.1K views 8 replies 5 participants last post by  masterse7en  
#1 ·
I realizes theres probably not a ton of top mechanics reading all these posts but theres gotta be afew..
Ive bin looking and looking and looking. I cant find anything that can show me what is stopping the crankshaft from being able to move side to side..
i looked at listings showing brand new sets of crank bearings and none the side walls. all have notches to hold them in place of course.. v8 engines have side walls on the end bearing to keep it from shifting sided to side. Not my r1.. some engines like harley evolutions have timkin bearings holding them inward..
Can some please help me understand what the hell is stopping these cranks from shifting and wearing out the block.
I know i gotta be missing something here.
The manual doesn't show things in super detail. an i really dont feel like pulling out the timing chain sprocket to see if theres some sort of bushing or spacer that keeps it pinned on that side and if thats the case then on the stator side another bushing which in theory would keep the crank from moving in either direction..
Please please im begging someone to help me understand this at least just a little bit.
hell if ur close enough to NJ ill buy ya a beer...
 
#3 ·
very well is possible. im not sure.
after i posted this. i went back over to ebay to look at the bearings and the cranks again. N i think a light bulb just turned on in my tiny little brain.. It kinda seems as though the bearing . sides and everything sit up inside the crank itself. now if im correct that would explain whats holding it in place.. if the notch from the bearing is in the block n the bearing goes all the way in the slot of the crank then the crank could possibly move either direction..
thats makes complete sense..

Id love conformation on this
 
#4 ·
Are you talking about a thrust washer of some sort? Kind of like suzuki does on their cranks? Because as far as i know there is no thrust washer or spacer on the cranks bearings. However there is a very slight allowance of space between the connecting rod and the lobes of the crankshaft. You should check with feeler gauges to ensure the clearance is within spec. But thats all i know of. Im by far no master mechanic, however im very familiar with the 06 r1 motor ive just recently completely rebuilt 2 motors. Hope this helps and i can give you exact spec if u need just not around my manual at the moment. Just let me know if u need it.
 
#5 ·
thanks for the reply and sorry for the delay in response..
the more and more i think about this. Im thinking its either the crank bearings themselves or the crank. 1 or both are probably worn a bit.. It looks like to me the crank bearings kinda sit inside a slot/groove in the crankshaft.. 1 of these is allowing the crankshaft to move back n forth enough to come in contact with the block/case..
Looks like in just gonna ride it for the rest of the season n pull n rebuild the whole motor.. I cant wait to be honest.. No better feeling then firing up a brand new rebuild engine uve done urself..this would be my first Japan made engine. cant be to hard with the help of the manual and the super awesome people here on R1 forum..Ive done 2 harley evo engines in the past 5-6 years..
Its also got me thinking now that im wondering if the noise people say there hearing coming from the Clutch. If its not really the clutch but the crank rubbing on the block like mine.. I never herd any noise from the crank rubbing just the noise coming from the clutch area...Plus with the clutch in i really dont hear anything. with it out i hear not a lot lot of noise but its definitely pretty loud enough to say somethings not right.. Id recommend when someone pulls there clutch apart to remove the plug from the cam sprocket cover and while rotating the crank look throught the clutch cover towards the crank where the crank comes super close to the case and look for scoring.. could very well be there noise..
thanks for all the help peeps
will keep the posted
 
#6 ·
the crankshaft has a machined section next to one of the journal bearings that sits against the case and keeps itself aligned. the cams also have alignment guides and the chain will keep the crank and cams aligned to each other somewhat. the clunking noise that people say is coming from the clutch isn;t actually the clutch itself its behind the clutch in the transmission. the transmissions are straight cut gears instead of helical like on cars so they make noise as the gears slap back and forth in neutral. if your bike is running just a little off it makes that noise ten times worse so synchronizing your throttle bodies will help with that. R1's are notorious for being loud.