Honda-SOHC

15 to 17 is a big jump, personally i would fit one of the bigger rears from cms to compensate

I would just go for the sizes used on the original bike on both the front and the  rear. Someone must do an aftermarket 35T that would fit Mo.

This was from the USA site ! Wonder if Oddjob is following it ... he had an obsession with collecting shells 

Quote from: MauiK3 on May 17, 2024, 04:07:29 pm
"I would not risk an Sohc four crankshaft to unknown bearings."


Reply from me:-

I agree but interesting that someone other than Daido would tool up to make shell bearings for a model 40 years out of production. People fit cheapo Cruzinimage pistons and rings,  so who can say that these are rubbish. Who is going to be the guinea pig though?
When i first got my K0750 there was an Australian firm selling undersize shells to fit a reground crank ...not sure on the depth of the hardening Brian. I have a scrap '69 K0 crank ...I could give it to Graham Curtis to determine the depth of hardening.

In the 1990's I designed a solenoid switch when I worked for Fenner (now SPX) fluid power based in Rockford Il. that we had made in Shanghai.. I chose some expensive precious metal contact tips made in France but the boss man found some at a  fraction of the price of Chinese domestic manufacture. I poo poo'd the idea of using them but the boss told me to make ten samples up using them and test them to destruction ... amazingly they passed all of the qualification tests.

I have often wondered if Daido would sell these shells direct as they are still in business supplying Honda etc.

HONDAMAN  ..had this to say :-

"The OEM bearings were (and still seem to be in the ones I've bought in the last year) Babbit alloy, both for the SOHC 750 and 550 I just rebuilt.
These bearings originally came from a Mitsubishi engine (rumored to be in a forklift engine made back when), Honda didn't invent them, nor their sizes. Honda made their cranks to fit commercially-made bearings, both the needle, roller (like CB450) and SOHC4 plain types - circa 1960s!

My local machine shop said they could probably find some bearings for these cranks even if Honda quit supplying them: they said they appear to be a common size, whatever that means? Someday I'd like to investigate that."



I always assumed they were made by Daido but i do know Mitsubishi made Honda valves ... Perhaps Trigger will know.

De gunge the bad bits and paintwith smoothright or similar but you willhave to opeup lower yoke a bit so as not to scape paint off, the rest of the i thin will run ok but cant get close enough on pics. I replied to your pm with a fix for the seal ares if needed

That's exactly like mine Mike, pitted below the lower triple by around an inch or so, I think Julie has a good plan there, use it now but send them off during those miserable winter months

Thanks Julie and Bryan. Bryan I will PM you.