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it baffled RB

Posted: Tue Nov 15, 2011 9:20 pm
by downpipe3
abouit 18months ago i met up with someone called chris at the ace cafe who had a real mint 69 h1 lookalike ,it was a h1a dressed up to look earlier and it was nice but ran like a bag of shit.
anyway the bike ended up at my house i spent probably 40 hours trying to get it running right i posted on the club site and believe me i tried everything .
so if your thinking did you try carbs , pipes i will say yes even RB came by and we fooked abouit with it but we couldnt get it to run past 5500 rpm it just hit a wall.
RB was baffled and so was i , chris took it back and in the past year he tried former drag racer pip higham who couldnt get it running any better
in the end the bike went too a company called pdq who have a dyno
£500 later it was diagnosed that the crank was twisted by 3mm !!
hence the phone call i got tonight, so its got to be stripped and rejigged
chris ritchie expect a call !! not from me though the owner chris is very capable of stripping it

i just feel relieved that the problem has been found

Posted: Tue Nov 15, 2011 9:41 pm
by robh1f
:shock: :shock: how the fuxx did that happen then......was it a shite rebuilt crank doya think?? :?

Posted: Tue Nov 15, 2011 11:15 pm
by bbb
Some sort of partial hydraulic lock??
Timing way out on one cyl??
Musta been something wierd!!
Many years ago, working as a race mechanic on the MBA125, if the crank was out just a couple of thou it would knock 3-400 RPM OFF it's max revs of 14800! Whip the crank out, stick it in a jig, welly shit out of it with a copper mallet and hey presto, full revs again!
(I really mean judicious taps of course!)

Posted: Wed Nov 16, 2011 5:29 am
by JA - Moo
I have a feeling there is something more going on.......

m

Posted: Wed Nov 16, 2011 6:38 am
by downpipe3
JA - Moo wrote:I have a feeling there is something more going on.......
we will see when he pulls it out but i have never rode such a gutless h1 it would hit 5ish and just run flat

Posted: Thu Nov 17, 2011 2:39 am
by h2chris
If he is sending it to me for rebuild I would love to check it out as I've never seen a twisted H1 or H2 crank. Perhaps it had been rebuilt badly and just pressed together out of phase?

The only thing that makes me suspicious is surely you would have had the timing marks way off if it was that far out?

We will see......

Posted: Thu Nov 17, 2011 3:05 am
by JA - Moo
h2chris wrote:If he is sending it to me for rebuild I would love to check it out as I've never seen a twisted H1 or H2 crank. Perhaps it had been rebuilt badly and just pressed together out of phase?

The only thing that makes me suspicious is surely you would have had the timing marks way off if it was that far out?

We will see......
A crank rebuilt too many times can slip, as the pin holes get loose.

m

Posted: Thu Nov 17, 2011 5:53 am
by downpipe3
h2chris wrote:If he is sending it to me for rebuild I would love to check it out as I've never seen a twisted H1 or H2 crank. Perhaps it had been rebuilt badly and just pressed together out of phase?

The only thing that makes me suspicious is surely you would have had the timing marks way off if it was that far out?

We will see......
he was gonna give u a call chris
if i remember right the early h1 can only be timed on 1 cylinder due to the rotor ignition set up early cdi or am i wrong ?

Posted: Fri Nov 18, 2011 2:32 am
by h2chris
John,

I know the crank pins can become worn & not very tight. I was thinking about how the journals were may be pressed together wrong as I've not seen them rotate under use before.

Gary,

I don't know how they work! :oops:

Posted: Sat Nov 19, 2011 10:33 pm
by JA - Moo
h2chris wrote:John,

I know the crank pins can become worn & not very tight. I was thinking about how the journals were may be pressed together wrong as I've not seen them rotate under use before.
That's another cause also!