Sachs tuning success

Finally got the tuning on my sachs sorted out.

70cc athena kit on a balboa, 19mm PHBG 85/50/60 (50 pilot is way rich, need to order a 40), derestricted SPX alsil pipe, 44/13 gears, 2.25 17" savas on snowflakes, trailtech cht gauge, general hydro forks to add some trail/rake in and make it handle less sketchy.

52mph top speed on a short downhill, 50.5mph on a short flat, all GPS. Still pulls up hills. 348 degree top CHT.

Think I can run a slightly leaner main and a little more advance to eek a bit more power out, but super stoked I broke 50. Was stuck at 40 for forever, but kept dialing it in. Got it running good and hit 42 with stock gearing then ground the cases down to put on the 13 front and gear up.

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Re: Sachs tuning success

How long do you expect the crank to tolerate 11,000 RPM's?

Re: Sachs tuning success

Probably Fred /

That's so good I'm jealous!

I couldn't get my sachs 1 speed clutch to last very long with a 80cc reed kit and pipe without it slipping. In fact it would slip many times Unless I rolled on the throttle, I could never nail it. I would have to mess with the clutch like once a week with new pads/sand pads, plates, preload shims and resecuring/securing the nut.

What are you doing for a clutch is it just stock?

With Just a stock clutch mine gave up the ghost after a week (well one 1 mi long uphill is when it broke) then I was messing with it from then on .

Post your clutch setup

Re: Sachs tuning success

Long enough to last until I get bored and rebuild the bottom end, then I'll throw one of these in it

Re: Sachs tuning success

The 70cc kit is milder than the reed kit, which I think helps my clutch.

I have had my fair share of clutch issues and I can't say my setup is reliable yet without putting more miles on her. At the moment I'm running a standard 2 pad/3 plate setup with very tight preload (still idles, but just barely in spec), red loctite on the nut, and I'm trying 80/90 weight gear oil instead of ATF type F.

I started milling down some extra parts to make a 3 fiber pad/4 plate "superclutch", but don't have a good bench sander so milling them down sucks.

I have a plan to make relinable friction plates like a motorcycle clutch, thin enough that I can easily run 3 friction plate/4 metal plate, over the winter. Already started prototyping this, I know the exact dimensions and have verified the materials I want to use work as clutches. I'll post an update after I experiment with this more and find something that works well. If I get this running well I'll get one of the higher RPM engagement clutch springs too and rebuild one of my donuts, that would be my ideal clutch setup.

Re: Sachs tuning success

yeah dude you're on the right track. 50 is damn good

i think the stock crank will be fine, its the nicest stock crank in all of mopeds. roller bearing, really nice quality... they are great cranks.

Re: Sachs tuning success

What dimensions are you thinking for your 3 friction plate/4 metal plate setup?

I am interested in going that route.

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