SOHC.co.uk Forums > CB350/400
CB400F Frustrations - Not firing, low compression (Cyl Block now off)
ManicGTI:
Well, after a hiatus from the bike I've managed to get outside and spend some more time on it.
Compression isn't looking good at all.
Dry Compression: 105, 0(!), 125, 110.
Wet: >200, 5(!), ~160, >200.
I did three of them with some oil and they increased massively, with the exception of the second which blipped only a little.
So I'm assuming from this that I have a major issue on Cyl 2 (Where cyl 1 is the 'choke' end), Ring, piston or knackered valve/seat?
From my trawls across the web, It should still be 'attempting' to start given the pressures above (with exception of cyl 2!), even if they are less than ideal. So I think I need to take a look at the carbs again.
I have to admit I'm starting to regret taking on a bike like this now, I just haven't had the time to give it he attention it needs :/
tom400f:
Are you getting the bike up to Canonbury soon? We can get together, draw in our breath and rub our chins over it...
ManicGTI:
So happily I've now moved to Canonbury...Sadly however the bike and all my tools are now in a garage in Hertfordshire as I don't have the room for two bikes here. If you see an Orange Street Triple R around say hi, that's me!
I'll have to sort a trip up there at some point to do some more detailed diagnosis. I was very close to buying a replacement engine from bikepusher but decided there's no real loss in tearing down what I have before I do anything silly. Head off first to inspect the valves, then poss the cylinder block off for further inspection. Down the rabbit hole...
tom400f:
Head and barrels off is easy on this bike and will tell you a lot. Out of interest whereabouts in Hertfordshire?
ManicGTI:
It's up in Cuffley, my Sister is living there and has an empty garage, well it was empty...now it's full of my stuff!
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version