ORIGINAL: downunder
ORIGINAL: Motorboy
Moki M5 10 cc and were made in 1970 and about 1400 were made.
That seems like one heck of a great find and I'd think it'd rate right up there with the legendary chromed bore ST 60 from about the same era.
AFAIK Moki never copied anyone.
I know, I know, I'm quoting myself but I was googling for some info on a Moki M5 and came across this long forgotten thread. So why was I looking? Because I saw one on e**y and thought Hey that looks neat. It arrived today
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The bearings felt like rubbish so I knew it was strip down time. I'd have done that anyway
. But what a cow of an engine to strip. The wrist pin most definitely has to come out of that plug in the back of the crankcase and that took some struggling because it was a quite tight in the piston bores. With the crankshaft out I checked the front bearing and it was a smooth as silk but the rear bearing grated and ground so I figured I was up for a new bearing. But do you think I could get it out? No way...I tried everything up to and including making a special puller from a Dynabolt to lock into the inner race. In desperation I dunked the crankcase and bearing in a warm solution of dishwashing powder and in about 1 minute the bearing was a smooth as the front bearing. It was only gummy castor after all
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The piston and ring looked very good but I can't say the same for the liner. It was about .5mm out of round with plier marks around the top land. No wonder it was tight coming out of the crankcase. Luckily the engine came with a spare piston/rod/liner assembly so that's now been fitted and with a little fuel it's got very nice compression (feels the same flicked in either direction too).
Tomorrow I'll be doing some measuring of bore, stroke and timings to add to my list of engines. Jens...mine doesn't have any engine number like yours does.
Edit to add..I just found some photos of another M5 but it's slightly different. There's no bridge in the exhaust port and the head appears to be cast instead of machined. Also it's been assembled wrong...go find it
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http://fuhur.rcmodell.hu/Muzeum/Muze...M5/Moki_M5.htm
And for Hobbsy...seeing I just saw your next post when I went to do this edit...yes, my engine is the same as Jens' with a minor difference in the prop driver and mine has the exhaust bridge drilled and tapped.