wrist pin rub

[thrownchain]

This is what happens when the wrist pin clip comes out or isn't installed.

[Bert44]

The marks look like there was never a clip in place and the pin has been marking the bore. Was there a clip somewhere in the crankcase?
Do you know if circlips can be used instead of the original clips. I think they are less prone to come out as there’s no extended tang.

My Wombat has similar rust staining and I’m hoping when it’s honed, that it will clean up to at least as low as the ring travel ( 30 mm from base gasket) as the piston is perfect.

[Bullfrog]

Dang! The cross hatching of the honing looks mighty fresh in one of the photos, lending credence to the concept that the wrist pin clip was never installed. Those grooves may have eaten ALL the remaining life in that cylinder . . . but I've got my fingers crossed for you thrownchain!
Ed

[thrownchain]

I also noticed that the cross hatch looked fresh, and no, there is no sign of the clip. Single ring piston, other than that the motor looks good. I hope a bore will clean it up, but may have to jump a couple of sizes to get there. If not I may have to source a new cylinder. Long term project, may show up at HD as a fresh rebuild.

[Bullfrog]

PS: I have NEVER had a Hodaka wrist pin circlip come out or break. (just sayin')
Ed

[thrownchain]

I've been working on motors for 40 years and have only seen a wrist pin clip fail or end up in the motor twice, both in motors that the owners abused heavily. One I know was caused by improper install as the clip on the other side was not in the slot in the piston, was not seated. The other I found down in the crank area, but it tore up the piston and cylinder to get there.

[Joe Ormonde]

What would have been a total bummer is if the Transfer Port was opened up to 13mm and the Piston Pin was 12mm. Use your imagination! The Engine spinning at WARP SPEED and the Pin entering the Port. I`ve seen what happens to a Hodaka when one of the Crank Thrust washers comes apart and gets eaten up by the engine BUT a Pin in a Port would be the ULTIMATE! And that`s what happens. One thing leads to another! Joe Ormonde.

[thrownchain]

Popped the piston off the rod and there were no wrist pin clips in either side, also the piston is stamped. 060. Single ring. DPO warning.