Hi
I made a thick head gasket from 2mm copper sheet.
This is because I am unable to fit the pushrods, the inlet side is now OK after lifting the head a shade, with loose head bolts.
But, the head needs to be torqued before the exhaust rocker gear is fitted.
I am still unable to fit the exhaust pushrods.
It has been suggested in other forums to remove the end caps and shorten the ally to suit.
But not overkeen on doing this, so how about using B50 exhaust pushrods, which are I believe 3/16" shorter?
Are they compatable?
On another note, when the head needs to be re-torqued, you have to remove the exhaust rocker gear?
what is the situation with the motor? was it complete prior to removing the head, was it a runner, or is it a bitsa?
reason for asking is that if it was a complete motor before then they should fit after. if it was in bits then is there a site with comparible lengths.
if it was a complete motor there may be something else amiss. I re timed a bike recently and on doing valves it was all or nothing. XL185 Honda 1980 vintage.. found out after re checking timing unit (originally a broken item) that I had put it in 180 degrees out. re positioning it made clearances correct.
The bike is a USA import, been stood for years.
The engine has been rebuilt, re-bored +.020", head has been refurbished with new guides, seats, valves, etc by the "Cylinder Head Shop".
Camshaft and followers new, as is all bushes/bearings.
When originally disassembled I had to loosen the head to remove the pushrods, but firstly the pistons needed to be freed.
then, as I understand they should be the right push rods as long as not too much has been skimmed from head and face.
presumably camshaft is same profile .
do the rods move on the cam shaft freely when turning crankshaft over, they might not be bedded down or followers stuck
Chaz, thanks for the reply.
The camshaft is a new spitfire profile.
The pushrods lift on the tappets nomally.
I think the head was skimmed during the head work, but I dont know by how much.
I'm thinking A50 exhaust pushrods, because A50 is shorter stroke, rather than shortening the A65's.
Hi. :) :)
I have just had the opposite problem; my rods were too short(this is a bitsa) so I have fitted longer ones. So my shorter ones probably A50 are available if you would like them. I'll do you a swap if you think that will help.
You are right, don't cut yours if you can possibly help it.
Mike 8) 8) 8)
Hi JulianS
Interesting, never thought of that! Fiddly job.
I will give it a go, presumably there is a point in 720* cycle when both exhaust valves are closed.
With the pistons going down, one is on its induction stroke (ex closed 0-180), the other is on its power stroke (360-540) where the ex begins to open at 102*(462*) ATDC.
So I think there is a window when both ex valves are closed between 397* (ex closes at 37* ATDC) and 462*, turn engine to ~429* on the power stroke?
JulianS, your post has disappeared, but many thanks anyway.
Job done :)
But it's not an easy job, especially with limited movement with the pushrod cups onto the rocker arm.