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Hey All,

heres hoping you all had a great new year? I see our cousins in the US are suffering badly with the cold (bloody arctic blast!!) I hope you're all safe and well?

I purchased a non running 06 r last year that was just supposed to have dropped an exhaust valve but it turns out it was probably the most unloved bike in history!! (the multiple previous owners I guess must have been neandertals because I don't think one of them maintained this poor sorry state of a bike (and especially the engine!).

I've split the engine and found a hell of a lot of metal debris in there (prob more than just valve shards) and a blanket of mud in the gearbox side of the motor (they must have run this thing with no air filter in a sand storm!!). Anyways enough complaining! The right side casing looks to have what appears to be cracks in it (I'm hoping they're casting marks but where they are would be consistent with a dropped valve pushing the crank down in the case) - let me know what you think from the pics.

here's a few pics of what I've been talking about.

Marks in casing (they're between the 5 to 7 o'clock position). If they're cracks whats my options? weld or replace?


sundry pics of swarf and muc

An obvious candidate for complete rebuild of tranny side. What does the motor side look like, upper and lower cylinder? Casting marks look OK, bet if you hit that area with a pc. of emery cloth it would disappear.

speechless.

motosicko wrote:An obvious candidate for complete rebuild of tranny side. What does the motor side look like, upper and lower cylinder? Casting marks look OK, bet if you hit that area with a pc. of emery cloth it would disappear.

Cheers for the reply MS - the cylinder apparently was a right-off (never received it as the guy I bought it off gave me a used replacement thats serviceable) the head was pretty chewed up so have a used replacement.

Yep the tranny side needs a complete rebuild (the clutch bearing is seized solid!).
I'll try the emery cloth to see if it removes the suspicious looking marks - thanks for the advice.

pics of the head - apologies for the poor quality!

riddler9 wrote:speechless.

you and me both riddler9 - you just can't believe some people have that little respect for mechanics!!

cheers
Deacs

Casting marks look ok.
Everything else is FUBAR.

Ok looks like I've found where the extra metallic shards came from . It looks like the the cranks has spun some debris around the case and cracked off a part of it as its come round! Does this need repairing ir can I get away with it? (i.e. will it cause cavitation and starve the big-end?).

pic of it:




Secondly - the moron I brought this bike off had mentioned that he tried to get a three pronged puller on to remove the stator rotor (it hadn't look like he had managed it as the oil journal didn't look damaged ... BUT ... it looks like he's tried to force something behind the rotor and has broken off the tab that is 'J' shaped!! (geez it irritates me when halfwits try and perform mechanics when they have zero knowhow!!! ) sigh!!

Pic of what I'm talking about (again is this shaped like that for a specicif oil routing and if its not there will cause issues?)

Wow! 99% of us would be parting the remainder of that bike out, or trying to locate a fresh motor. Costly rebuild for an 8 year old bike. You can find good running 06 for $2000.

124 wrote:Casting marks look ok.
Everything else is FUBAR.

yeah its a pile alright

motosicko wrote:Wow! 99% of us would be parting the remainder of that bike out, or trying to locate a fresh motor. Costly rebuild for an 8 year old bike. You can find good running 06 for $2000.

Yeah you're probably right I should but tbh what I'd get for it is prob a loss at the moment - My plan is to use the complete crank out of my 05 R as well as the piston set as it has no wear on it and then rebuild my 05 with all new (06 will get new case bearings however).
My plan is to convert it to a SuMo and then sell as they make a fair bit more over here in the UK.

That "J" shaped broken casting is what looks to me like whats left of the holder for the timing chain guide . it will need to be re-fabricated or the case replaced , otherwise nothing is there to hold the timing chain guide in place so you will not be able to get tension on the timing chain , as well as the guide will be rubbing on the crank and the nylon will be everywhere the first time you fire it up , not to mention the timing chain rattle then slipping then another valve thru the piston , without repair or case replacement , the motor will self destruct AGAIN very quickly

This MUST be repaired or replace the case , these are your ONLY options for this item

JimDirt wrote:That "J" shaped broken casting is what looks to me like whats left of the holder for the timing chain guide . it will need to be re-fabricated or the case replaced , otherwise nothing is there to hold the timing chain guide in place so you will not be able to get tension on the timing chain , as well as the guide will be rubbing on the crank and the nylon will be everywhere the first time you fire it up , not to mention the timing chain rattle then slipping then another valve thru the piston , without repair or case replacement , the motor will self destruct AGAIN very quickly

This MUST be repaired or replace the case , these are your ONLY options for this item

Hi Jim, thanks for your reply. Yep I see what you mean (I should have just looked in the manual first time round I'll have to consider myself a mechy moron for that one).

I'll see if I can find a ali fabricator round my area. Thanks again for your input.

cheers
Deacs

No problem !

If you attempt to have someone fabricate something , make sure it follows the same path and width of the stock setup and is ground smooth inside so the tensioner wont bind up , look in the manual , or better yet see if you can look at another case and take measurements and/or pictures and make a actual size diagram/template for the guy to follow if at all possible , it needs to be the same size and shape or you might have issues with the flywheel or timing chain rubbing or the crank sprocket not fitting

Which is why a new case or used EBay case might be a better idea (and possibly cheaper) , personally i would go with a used EBay case if it were my motor

Yep I agree, I was also wondering about the tensile strength of a repair like that - especially where something like a chain tensioner bar would be bracing itself against it?!

Jim what are your thoughts on the broken tab on the flywheel casing? Do you reckon if that was left it may causing oil flow issue (e.g. cavitation)?

pic:

That engine is done, your crank twisted and that's the wrecking path it took.

I wouldn't even consider re-using those cases, or attempting to repair them.

I am a professional metal fabricator, journeyman welder proficient with alloys and a lot of experience working with engines and motorcycle fabrication... You will waste your time and money "fixing" it.

I'm not telling you this to be negative, I just hate to see a guy struggle with something like this.

You could find case halves on e-bay fairly cheap and be miles ahead of where you'd be trying to repair an engine that has essentially been through hell.

Yea , i pretty much agree with sand.man on this , in the long run , it will be much easier,safer,and most likely cheaper to go the EBay route

Cheers Lads, appreciate the advice.

Deacs