Sachs G3 1979 Speed increase help

Hey, I'm new to mopeds and was wondering how I could increase the top speed of my moped without upgrading the engine or changing the exhaust. I get about 30mph

with pretty slow acceleration. Any ideas

Re: Sachs G3 1979 Speed increase help

ᴛᴇʀʀʏ ᴅᴇᴀɴ /

without changing the pipe or upgrading the engine? lose some weight

Re: Sachs G3 1979 Speed increase help

First you need to kind out what engine you have.505a/c or d.

Sachs are great stock bikes but pretty much the worst for tuning. You can't just throw a 70cc kit on it like a Puch...well you can, but your clutch will go kablooie.

Hopefully you have a 505d. Those can be made to hit 40 relatively easily with an expansion chamber and carb work.

If not your kinda stuck with what you have without alot of expensive parts and modding. (edited)

Re: Sachs G3 1979 Speed increase help

Look on the right side of the cylinder, the top horizontal cooling fin, a lot of the 505s have the speed rating of the cylinder cast in that fin unless it is a D. The engine ID on the right side of the engine casing will tell you if it s a A C or D. D the fins are square and the A C are tapered toward the front of the engine.

All Sachs engines can be mildly ported and take a better carb & intake with a derestrited exhause or aftermarket pipe to give you more than 30mph. Also a goodly tune up of the engine and the entire bike will improve performance and reliability.

If you need anything more than a bit of improvement and you will be spending a few $$$ or more.

Re: Sachs G3 1979 Speed increase help

Just get the 3 speed hand shift 505/3bx and some odds and ends off treats, those Sachs rip. I built this 9 years ago. Man time flies?


Re: Sachs G3 1979 Speed increase help

Whoa Nick back in the game?!

are there any mammoths left?

^That is almost unquestionably the fastest sachs.

Anyway, there's a writeup on almost everything you need to know and i think it's up to date... The Airsal 70cc kit is only 5 or so years on the market and not bad for keeping clutches intact.

it's a lot to read but all worth it, covering simple upgrades to carb, intake, jetting, the different exhaust options and more.

Easiest upgrade would be a clamp on pipe and upjet to match with less air filter. A little lift to the intake gasket and a dellorto SHA 14:12 or 14:14 carb is a nice upgrade with more easily available cheaper jets for tuning and a simple click choke. An airsal 70 kit is a nice simple to use kit, and if you wanna go nuts folks have bested 60mph with the 2 or 3 speed manual shift motors from germany coupled to the 80cc athena reed kit, custom or peugeot exhausts and big ass 20+mm carbs. That destroys clutches but if you want big risk and big rewards it's a wild ride, and easily available manual gripshift is a pretty unique cool option in mopeds

My favorite setup on sachs has been a 2 speed manual gripshift D motor, gutted stock pipe (or better yet the alsil quiche) and stock intake with a 15mm bing, geared up to 13x42 or 11x35 (ish). It's dead simple, reliable and efficient with speeds low-mid 40s and good take-off from the line. andcost, depending on what you're starting with, is just a few hundred.

I also have basically that setup for sale, on a bike, for 500 - if anyone interested...,4310099

Re: Sachs G3 1979 Speed increase help

i got a 504, the take off is decent, u might wanna plug your decomp if it sounds poppy/boggy. hmm clean your exhaust, maybe regear depending on what yr looking for.

Re: Sachs G3 1979 Speed increase help

The g3 can handle a smaller rear sprocket pretty well as long as you aren't too heavy. That d motor makes good torque.

Re: Sachs G3 1979 Speed increase help

Alex Fredericksen /

Airsal 70cc, 15 Bing, Alsil Quiche. Easy, quick, cheap, RELIABLE.

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