It's not as bad as it could have been. Before we set off from Aylesbury on the BOTAFOT on Sunday, PC had mentioned he had a bit of a rattle coming from the motor, and put it down to a dodgy camchain tensioner adjuster. He rode the bike along the A413 and A422 for about 25 miles before it slowed down drastically and then stopped, then it wouldn't start. After PC got the bike to PixieCentral in the 'window-licking-good' Transit we took the rocker cover off to find some errant parts swimming around in the head. It was very apparent that the right inlet valve tappet adjuster had wound its locknut off and then the adjuster itself had made a bid for freedom. That would explain the rattle. After this had happened, it's my guess that the rocker on its own was smacking down on the valve cap at a funny angle and caused the collets to pop out and the valve to drop. Luckily the valve collets were still up top along with the adjuster screw and locknut. It was obvious that the inlet valve was bent, cos it wasn't going either up or down, so the decision was made to remove the head and survey the damage caused deeper down. The head came off tonight in about 1/2 an hour, and what a lovely bike it is to work on. Everything is accessible, and comes apart with the minimum of fuss, it's almost like working on a much newer bike. Ater a swift but gentle tap on the valve stem ensuring its removal, it turns out that as well as the valve being bent, it's broken the base off the valve guide. There is also what looks like a crack up the length of it, so that's going to need replacement as well. The piston itself has only lightly kissed the valve, and shows just a little marking that will polish out, but the combustion chamber has some pock marks in it where the valve guide remnants have been smacked into it when the piston was at TDC. I will be able to get those out using a hand tool of my manufacture, similar to a scraping tool. I've done this enough times on RD heads that have had broken rings jammed into them. All I need now is to find someone to press a new guide in, I can get the old one out easily enough. So that's the score: A top-end gasket set A valve guide An Inlet valve A pair of collets Some remedial work on the combustion chamber Job's a good 'un -- Lozzo ZZR1100D, GPZ500S, CB250RS BOTAFOT#57/70a, BOTAFOF#57, two#49, MIB#22, TCP#7, BONY#9, ANORAK#9, DIAABTCOD#14, UKRMT5BB, IBW#013, MIRTTH#15a/16, BotToS#8, GP#2, SBS#10, SH#3, DFV#14, KoBv#3. Url for ukrm newbies : http://www.ukrm.net/faq/ukrmscbt.html www.mjkleathers.com
I did. I had put it down to the camchain needing tensioning and you posted instructions on how to do it. I followed these instructions and that seemed to sort it. On the morning of the 'FOT, I pointed out to Loz that the rattle had returned and I suggested that the camchain tensioner was sticking. Loz said that he would show me how to unstick it after the run, the rest is history. Ultimately the reason the bike broke down is due to me not checking the simple things first.
Bad form etc. I've phoned z-power and they have all the bits except the inlet valve which is listed as 'no longer available'. They gave me the number of Cradley Kawasaki and the end result is the same :-( Anyone know where I can source an inlet valve for an '81 Z400 G1?
Erk. It's a fully manual tensioner, so it never, ever sticks, not like the modern Kawasaki ones. Oh well, you live and learn.
The Older Gentleman had a fit and wibbled..... I wasn't aware of this beforehand. I am now i've stripped the top-end down. Every day's a school-day -- Lozzo ZZR1100D, GPZ500S, various CB250RSs BOTAFOT#57/70a, BOTAFOF#57, two#49, MIB#22, TCP#7, BONY#9, ANORAK#9, DIAABTCOD#14, UKRMT5BB, IBW#013, MIRTTH#15a/16, BotToS#8, GP#2, SBS#10, SH#3, DFV#14, KoBv#3. Url for ukrm newbies : http://www.ukrm.net/faq/ukrmscbt.html www.mjkleathers.com
petrolcan had a fit and wibbled..... Lets hope not, otherwise the collets and guide you ordered will be surplus to requirements -- Lozzo ZZR1100D, GPZ500S, various CB250RSs BOTAFOT#57/70a, BOTAFOF#57, two#49, MIB#22, TCP#7, BONY#9, ANORAK#9, DIAABTCOD#14, UKRMT5BB, IBW#013, MIRTTH#15a/16, BotToS#8, GP#2, SBS#10, SH#3, DFV#14, KoBv#3. Url for ukrm newbies : http://www.ukrm.net/faq/ukrmscbt.html www.mjkleathers.com
petrolcan had a fit and wibbled..... Should be back on the road on Wednesday evening then -- Lozzo ZZR1100D, GPZ500S, various CB250RSs BOTAFOT#57/70a, BOTAFOF#57, two#49, MIB#22, TCP#7, BONY#9, ANORAK#9, DIAABTCOD#14, UKRMT5BB, IBW#013, MIRTTH#15a/16, BotToS#8, GP#2, SBS#10, SH#3, DFV#14, KoBv#3. Url for ukrm newbies : http://www.ukrm.net/faq/ukrmscbt.html www.mjkleathers.com
