No.17 - 2017 race bike

[CB1pod70]

Despite the race season fast approaching, I've really been struggling to get up the motivation to go out in the garage for the last couple of weeks but I have made some progress...
Steve mentioned when I bought the bike that he thought there might be a problem with 2nd gear and he was getting some shuddering in 2nd. As I stripped the bike down before really riding it, I figured I had better investigate this and as you need to split the crankcases to get at the gears, I might as well give the engine a thorough check over and investigation while I was at it.
In no time at all I was down to this


Impressively there was very little sign of wear in most of the engine with the bores, rings and bearing shells all showing very little wear. The clutch basket and centre were heavily notched as you would expect from a race bike and the middle gear selector fork had bent and was heavily worn (forgot to get a photo of this) which I'm hoping was the cause of the 2nd gear problem. Surprisingly there was very little wear on the gears and dogs so hopefully this was the cause of the problem.
With the initial inspection out of the way it was now time to invest in some new gaskets & seals and start the long and tedious task on degreasing, cleaning and measuring everything (This probably contributed to the current lack of enthusiasm....)

I found a good used selector fork from a CB-1 in the spares stash and set about reassembling the bottom end. Something else that was also apparent is that the sprung tabs in the selector drum where in back to front so these were swapped round and eventually I had the bottom end back together. Everything was spinning freely and all the gears were selecting smoothly but until I ride the bike and the gearbox is put under load, I won't know if the issue has been fully resolved.

Here is where I'm up to so far:


The valves have all been popped out of the head and given a light lapping in with new (Chinese) stem seals and so tonight's task is fitting the head and setting the valve clearances. Hopefully I have the correct shims to hand.

After all this, I know understand why engine builders charge what they do, I've lost count of how many hours have gone into the engine so far and did I mention how tedious the cleaning was

[nc23rider]

Hi, 2nd gear was not the problem, it was when in 5th going round gerards under full power that I got the feeling the
chain/gear was snatching/slipping hence why for my last two meetings I geared it to only use 4 gears.
hope this helps.
steve.

[CB1pod70]

Thanks Steve, I was convinced you had said it was 2nd but it was a while ago Didn't find anything obviously wrong with 5th so fingers crossed all will be ok.....

[CB1pod70]

Not much progress to report at the moment as I currently have my left arm in plaster as a result of falling off the pike bike at Stretton circuit and fracturing the scaphoid bone (between the base of the thumb & the wrist). Looks like I might be missing the 1st round at Cadwell at the beginning of April.

All will be revealed when I go back at the end of this week for the next check-up.....

[CMSMJ1]

BUGGER.

Heal well chap