Roadrunner. The rebirth of the Honda C90.

About 5 years ago I had a C90 shaped itch to scratch. There was a guy at the other side of my village who had had a C90 in his garage for years. Some persuasion and £150 later and the non runner was mine.
No horror stories or anything, It just hadn't been started in a while. A new battery went in and it started first kick. No joke.
I gave it an oil change, got it an MOT and off I went. 

We went all over the shop

then one day on the way home from work my C90 died. A few kicks later it fired back up, but would splutter and die at high revs. I got it home and gave everything a look. The exhaust tappet was tight. I got the feeler gauges out and reset the gap, but I fear the damage was done. The C90 ran on for a while longer but became increasingly difficult to start.

Getting if flat out on its way to another MOT won’t have helped....

Then one afternoon at a drunken party we were using the C90 to do a wee trials course. Some guy who it turns out had never been on a bike before took a shot and crashed bigtime. Luckily his body to the brunt of the tree involved in the crash, but the C90 had still done a big wheelie, smashing the rear mud guard.

This coupled with the starting issue meant the C90 had to get a lift home in the back of my mate Dave's motorhome.

I put in in the shed, and it sat there for nearly 4 years.

That’s not right. So I began bumbling my way through the rebuild.........

This was all pretty new to me. i know all the theory behind how engines work and guesstimated that the running problems and lack of compression was down to a knackered exhaust valve. It was still pretty daunting setting about the bike with only a Haynes manual for guidance.

Out came the engine.

 

I took the back end off too for inspection and cleaning.

Then I took the cylinder head off. It all came apart easy enough.

You can see that the exhaust valve is well shagged. At this stage I offended someone on a C90 facebook page by pointing out in a humorous (to me) photo that the valve was fucked. Sorry if that was you.

Fucked.

I stripped the head down.

I then (eventually) got around to ordering new valves. I got the exhaust valve off ebay but it turned out the guy sent the wrong one. Wemoto sorted me out with the right size valve and my uncle kept me right when lapping it in.

Greaser polished up the valves.

Sorted.

Now all I had to do was rebuild it and see if it all works.

I was getting slightly distracted doing up my other project, a BMW R1100S, but I focused my attention on the C90 and got started. The valved were lapped in and I was ready to begin.

Oh aye. Shite.

I forgot about those things....



Those things being valve springs and the fact they need compressed to re fit them and the valves.
After about an hour of trying to compress the valve springs with a ring spanner and only succeeding at pinging the collets (wee fiddly thing that hold the springs to the valves) all over the shed I gave up. It was back to the drawing board. I had just thought up an elaborate plan to use cable ties to compress the springs when my mate Dave seen what I was up to via Instagram. Through the power of social media I got my hands on a big set of valve spring compressors.

Cheers Dave.

I got the head back on, made sure the timing was OK and refitted the engine.

All wires and pipes hooked up and I wheeled the wee 90 outside.

I dabbed the electric start..


AND......


fuck all.

I got the kick start out.
















BRAAAMM

bu bu bu bu bu bu bu.

IT WORKS!!! I shouted "LOOK AT THIS! THE FUCKER RUNS!!!” through my neighbour's window. He was the first person I seen after the mighty 90 had burst into life. I don't know how much he appreciated my joyful news however as he was trying to have dinner with his in-laws.

Does it run? #C90 #shedlife #project #winner

A video posted by mike (@yodagoat) on Jul 23, 2015 at 2:17pm PDT

This is after I had calmed down.
I was over the moon.

It ran, but it wasn't legal yet. The drunken crash 4 years ago had destroyed the back end. I had sourced another one, but it was pitiful red. I got the black rattle can out and gave it my best shot. I was also missing rear indicators and footrest rubbers. I paid some money to the internet and my computer assured me parts would arrive soon.

Painting the new back end and that was it pretty much finished.

Comfy bits.

I was however left with these comfy bits (because you ask yourself where the fuck did they comfy? Do it with a Scottish accent)

MOT was booked the day after my indicator rubbers arrived. There was a wee hiccup when fitting the indicators where I thought my flasher relay was broken, but I had used too long a bolt to attach the indicators to the rubber and it was shorting out. Bolt cut down and it was off to the MOT station. I'm sure the footrest rubbers will be here tomorrow....

Waiting for an MOT

IT PASSED!!!!!
And the footrest rubbers arrived the next day. All there was left to do was ride my C90 once more.

Roadrunner was back!

There will be more to come on the C90.....