Tuesday, February 1, 2011

90 engine finished

My 90 engine is finally finished.
Last week I recieved the titanium valve spring retainers for my 90 motor so it was time to mount them and finish the cylinderhead.
Back when I compared SS50 valvesprings with S90 springs, I must have made a mistake somewhere, as the inner diameter of the outer springs differs.
This meant that the springs had to be "helped" a little bit to fit the retainers, but that all worked out.

Fitted together with PM/rocky valve spring set to cope with the high lift camshaft of unknown origin. As original springs would bottom out at this high lift and wouldn't give enough pressure for a high revving engine with this cam.

Further modifications of my engine include:
Lightened valves and rockers.
High lift camshaft.
Ported head with matching intake manifold.
Kei-hin CR29 carb. (the real old model)
53mm piston kit in alloy cylinder.
No rotor on cranckshaft anymore.
Close ratio 4th gear

all combined to form this picture:


  1. Damn! I love all the details you've put in there. Decompression dipstick, finned head covers, velocity stack, etc. etc. Looking forward to see how it performs with all the cool old-scool upgrade parts.

  2. En zet er eens een *grotere* foto bij.. idem van de rechterzijde..

  3. @ tom, the velocity stack came with the carb, luckaly, as you won't be able to find them loose.
    @ Ralph, bigger pictures should be made with a cleaner background, but that's not an option with a C110 engine also opened up on the workbench.