causes of inconsistent motor speeds? sachs foxi


I have my first moped for about 4 months now, a sachs foxi. I'm sold on mopeds and want to get more already.

I had a question about engine speeds on my bike though.

It seemed when I was riding that there was often a disparity between the speed I was going. I wasn't sure if it was because of different perspectives compared to other cars or hills or wind...but I often am riding on relatively flat ground and not too much wind.

Since the speedo is broken, I finally had somebody clock me and my suspicions were correct.

Sometimes the bike seems to max out at 20-24 and then out a random stop it then was going 30...then after the next stop back down a bit.

What would be the cause of this and what should i look into doing?

There is a ride down here in Orange County soon and I'd like to participate...though I don't want to get left in the dust if my ped is sticking at 22MPG.


Re: causes of inconsistent motor speeds? sachs fox

Micah Mine kind of did the same thing sometimes it goes like 30 and then other times it barely does 25.I tried replacing the plug but It doesnt help.I dunno what the cause is maybe my post will help you get some answers.

Re: causes of inconsistent motor speeds? sachs fox

Have you cleaned out your pipe yet?

Re: causes of inconsistent motor speeds? sachs fox

cleaning is the answer to every thing well ok at least making it back to where it started chain,timing,fuel lines, carb ,spark, exhaust, and if all else fails take the cylinder off

(disclaimer) NEITHER OF MY BIKES RUN PERFECTLY AND I KNOW NOTHING ABOUT THAT BIKE just thought u might wanna know before following my advice ask some one who really knows then if they r clueless try what i said

Re: causes of inconsistent motor speeds? sachs fox

BryAn eurism /

Easy, simple. Between slight head winds, going slightly uphill or downhill (it may LOOK flat), whether a big boxy vehicle next to you is creating an air pocket, and atmospheric pressure will factor in how fast or slow you go. The speedos aren't the most accurate in the world either.

I have a KTM Foxi ( the one that looks more like a Puch)

It has a CEV speedometer that reads about 7 mph fast, so when it says I'm going 35 I know I'm really going 28. If I get a good combo of speed factors I can push the needle up to 40, but I know there's no way an untuned Sachs can go that fast.

Spartas got a little more back, they weigh more so you'll never have great takeoff or hill power. But if you get things all just right they can go about 33 without swapping a single part

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