Crank time? Crashed..

[Kara25]

Hi all to say i am feeling crashed will be an understatement. Tore down today the bottom end of my engine to clean all the gunk out from relieving the upper case to accept 650 cylinders and my eyes saw THIS. I just cannot understand what happened. Last thursday my motor was running NORMALLY no sounds no clanking nothing at all went for a 35km ride and came back parked it in the garage to start the conversion.. Lost the life out of me after seeing this. Putting two pictures. Conrod No1 cylinder and No2 for conparison...

[Kara25]

[Kara25]

[zed1015]

Looks like the crank has spread at the pin.
Depending on the cause and whether the pin is loose in the web in may be able to be pressed back.
These roller cranks are prone to twist and benefit from indexing and welding especially in performance applications once the condition of the crank and main bearings are confirmed ok.

[Kara25]

zed1015 Thanks for the feedback man i am so stumped as i told above just 5 days ago this engine was running normally no ill symptoms it was hitting 130kms no problem i cant wrap my head around why this happened.. No knocking no noise nada. Are all 550 cranks interchangable?? Thanks again for the info

[Nessism]

All 550 cranks share the same PN, so that means that are the same. There are quite a few cranks for cheap on eBay. I wouldn't get down about this crank situation. $hit happens.

Edit: sorry, I forgot you are in Greece. Hopefully you can find a crank in your local market. Pressing it back together may be another option, but I'd be concerned it will come back apart unless welded.

[Kara25]

Well nessism from what i gathered here in the forums not all 550 cranks are the same! The early 77-79 have straight cut teeth on the output shaft and 80 onwards like mine they are slanted. Tracked down a 82 550M katana crank from germany with the rotor still atrached also. Seller claims 44.800 kms on the crank so i assume its good cant see it up close unfortunatelly but at least here are the pics Nessism

[Kara25]

[Kara25]

[Kara25]

[Nessism]

Well nessism from what i gathered here in the forums not all 550 cranks are the same! The early 77-79 have straight cut teeth on the output shaft and 80 onwards like mine they are slanted. Tracked down a 82 550M katana crank from germany with the rotor still atrached also. Seller claims 44.800 kms on the crank so i assume its good cant see it up close unfortunatelly but at least here are the pics Nessism

Ah, I see. Looking at cranks on eBay shows the difference in the gear. I wonder why the crank PN's are the same?

[zed1015]

zed1015 Thanks for the feedback man i am so stumped as i told above just 5 days ago this engine was running normally no ill symptoms it was hitting 130kms no problem i cant wrap my head around why this happened.. No knocking no noise nada. Are all 550 cranks interchangable?? Thanks again for the info

If the crank hasn't twisted out of line but just spread you wouldn't notice any problems and there's no telling how long it's been running like that.
It may even be the result of crank work performed by a previous owner.
I'd pull the crank and have it checked for overall condition and if the pin fit isn't loose in the web have it pressed back with the correct thrust clearance and then welded.along with the rest of the pins.

[Kara25]

No idea but those forums here again saved me from a potential wasted purchase. Nessism i know you swear by threebond 1184 for case assembly but i cannot find it anywhere what i find is threebond 1207B which people say that is the actual suzukibond just with different name. Any insight? Also about oil seals i got on order the RH crank one the LH behind the stator and 2 that go behind the gear shifter i think plus 2 orings for the oil galleries. Anything else that i should look for?

[zed1015]

I use this on all my road and race engines.
V-Tech VT-157 Vital Black RTV Silicone Instant Gasket Maker - 85g Tube | eBay
Just as good as anything else out there.

[Kara25]

zed1015 what you must keep in mind is that i dont have access to shops here in rhodes greece that can undergo that much sophisticated work. I have access to boring head resurfacing shops but cranks NADA... if i was living at athens that would have been another story...i dont know if i can sleep at night now that i have seen this gap in the No1 conrod. thats why i am thinking replacement. As for the case sealing RTV? i thought rtv is supposed to be the forbiden material to use on engines if thats the case i have a tube of Permatex fuel resistant gasket dressing its supposed to be all automotive fluid resistant and the product you guys know as Hylomar but with another name. What do you think?