Honda CT 90 Engine Rebuild Part 4 - It's Not Pretty

Work continues on the rusty 1969 Honda CT 90 K1 engine. I use my home made tool to remove the valves, examine the cylinder head & use a heat gun to try & remove the piston rings which are seized in place. With the parts list rapidly growing, this engine is heading towards the old sweeping brush joke. "I've owned this brush for 20 years, it's only needed 6 new heads & 4 new shafts." Meaning, how much will remain of the original engine?

[@perpetualmoto]

Another great "How-To" CT video helping us all keep our Posties FLYING!! Thanks Ranger!

[@Free_Ranger_CT110]

Thanks Brad, much appreciated!

[@marknott2084]

Thanks for this series. Very instructional for tear down tinkering and working out what can stay or needs to be replaced on my Postie.

[@Free_Ranger_CT110]

Thanks Mark, much appreciated. I do hope people find these simple videos helpful.

[@luckydog7299]

thank you for work you do on these old bikes

[@Free_Ranger_CT110]

Thanks mate!

[@donktec]

Thanks for another interesting video, looking forward to the assembly too.

[@Free_Ranger_CT110]

Thanks, I'm struggling to source another kickstart shaft so I can't start bolting it all up just yet.

[@3goldfinger]

Looks like a lot of fun

[@Free_Ranger_CT110]

I enjoy doing it Micheal but it's easy to spend more money than the engine is worth.

[@thenickabs]

a very minor point, but just to note that the large clutch set ring on some of the C90/CT90 clutches fitted in the 1960s only have one "ear" (I realise yours may have been broken, but just mentioning it in case others worry that their's is too). I'm really enjoying the videos, many thanks for doing them!

[@Free_Ranger_CT110]

Thanks, I didn't know that. I thought it was strange to be broken. As you said, there's probably nothing wrong with it. Too much time on ct110s & not enough on ct90s!

[@freetv77]

Is the head a complete loss? (As in, there will be no way to get the valves to seat properly due to rust? ) New pistons and new rings (non OEM) are pretty cheap in the US. The cylinders are not that cheap - especially OEM. I don't know about Oz, but is sounds like you have a spare head available. I look forward to seeing the assembly (valve guides, seals, springs, keepers). Do you plan on sticking with the original piston size (50), or will you bore it out and use something larger? (I think people go up to 58). Good luck and thanks for posting.

[@Free_Ranger_CT110]

Thanks for commenting, the head could probably be saved with some work, as you said I do have another head so I'll use that. Not sure about piston yet, the other engine is from an atc so it doesn't have a kickstart shaft which I need. Parts are hard to find here. And postage from overseas makes things expensive.

[@SpyAgentMan]

Excellent series best on the web.

[@Free_Ranger_CT110]

Thanks, I do try to keep it to the point & hope the videos help people.