.also, i am a twat
Joined: Jan 2008
So, WOW!?! - I had the misbehaving DMW booked in for 9AM, so I began trying to start it at around 8AM just to be sure, you know? In addition to giving me plenty of time so as to reduce the likelihood of Grrrrrrr Arggghhh Smashness, this was also with the aim of getting there early & giving it a chance to cool down because the symptoms were, as I’ve mentioned, worst at a cold start. Even after a night of trickle charging it was, as usual, resistant to starting but with a bit of prodding & kicking & tweaking of settings it eventually kicked into cackling life and I rode direct to Doctor Daves, getting there before the gate was even open. He was a bit surprised to see me, because, as you long term browsers will know I have always been something of a ‘night bird’ and have only recently discovered there’s a 9 in the morning too. Boom tish. Iiiiiii thannn’kew, I’m here all week…
I was, as is often the case, to be looked after by Magic Ian, and he knew just how to start – naturally by putting the kettle on. I let him settle in before beginning to feed him the symptoms & other info and, after the obvious carb discussion, the first thing he asked about was valve timing. In the spirit of letting it cool down we supped at our cuppas and shot the breeze a short while, then we knuckled down. Well, he knuckled down & after taking the tank off as requested I commenced wandering around the workshop apologising for my mechanical ineptitude while he dived into checking compression & the coils & HT leads/caps & pulling the plugs etc.
The right side wasn’t giving ultra brilliant compression, and the left was lower still so it was off with the rocker covers & front cover and prodding at the clearances before cranking it via the rotor bolt & checking them all proper like. FYI it’s a post 82 engine, assembled from a seemingly good condition late type short engine (£11 via Jake on ebay), Nikasil barrels & heads from another engine, with new rings @ the rebuild some 25k miles ago, so at least from a wear point of view one ought to expect reasonable compression, were all else set well & seated firmly. I could have checked the clearances myself, but given the same scarcity of tools & no adequate workspace as when I’d last set the clearances (in the rain in the car park here at The Place) I just wasn’t going to get it done & certainly not properly. Given the aforementioned working conditions when last I set the clearances there was most certainly the potential for me to have got them wrong. Also, see above & generally thru/oughout this entire thread for ample proof of regarding my mechanical ineptitude. So I didn’t think I’d set them myself. I thought I’d let Magic Ian do it.
The right side was broadly right & required only minimal tweaking to the preferred settings of Magic Ian*, and the inlet on the left was within spec, but the exhaust on that side was tight. It’s quite likely that I was being rained on while setting this one or may have lost my way in that part of the process or just plain got it wrong so I may indeed have thereby been contributory to the overall ‘not working’ nuisance I’ve been living with for the last few weeks, in the sense that while the engine could get away with the tight setting when all else was well and good, once the carbs & general other settings/electrics of the bike weathered with usage the clearance problem worked together with general wearing out/’other things I got wrong’ to make up the overall problem, if you see what I mean. I’m not proof reading this shit so if none of that makes sense you’ll have to work out what I mean, where I was wrong and what was right, write it down & send it back to me in triplicate. Thank you.
There is of course the potential for a variety of issues, should the clearances wander out again, which we chit chatted as variant possibilities while Ian carried on checking this and adjusting that, but once he’d tweaked the rocker block bolts down on the left head** and got the valve timing where he wanted it there was better compression, equal to the right, and so we moved on with the process.
Originally Posted by planktonnn
* Somewhere in the middle of the book variance.
** I thought I’d got them torqued all happy and such, but he was able to pinch them down by a little. The right side was ok.
...using the wrong spanner since 1964...