PLEASE HELP: Moby hissing and back wheel shakes on advance

Problem #1: My Motobecane Mobylette is at it again. This time while riding yesterday I thought everything was fine. Needless to say, I was wrong. As the night continued my bike started hissing bad, to the point where it sounded like boiling water. I thought it was the brake line but reading some articles online. I became paranoid to think that it might be an air leak.

Problem #2: I said in a previous thread that on take off from a stopped position my Moby would have a hard time advancing. To the point where it would sound like clutching into in between gears on a car. Well I noticed last night that the back wheel shakes like a demon before it gradually advances forward. What could this problem be?

Problems just seems to be happening one after the other and really is testing my patience. If anyone has any idea what this could be I will be eternally grateful.

Also, I will be putting up a video tomorrow.

Re: PLEASE HELP: Moby hissing and back wheel shakes on advance

hissing? like when? while running, while moving? you should be able to idesntify if it's related to engine rpm or wheel motion, could be something rubbing, wear in the clutch, or possibly related to #2

shaking rear wheel shouldnt happen unless it's loose or the bearings in the hub are loose. try'n tighten it, if that doesnt help pull it off and tigheten the hub with a cone wrench.

"Problems just seems to be happening one after the other and really is testing my patience"

this is mopeds.

Re: PLEASE HELP: Moby hissing and back wheel shakes on advance

Yeah I don't know what you mean by hissing?! I don’t think an air leak would be audible above the engine noise? I am not sure though because I have not yet had the pleasure of having an air leak… this will help with the where and how of checking for air leaks:

http://www.mopedarmy.com/wiki/Air_leak

Could well be something rubbing like Will said in which case have a real close look over the bike while on the stand spin the wheels etc try to isolate where this hissing comes from, hopefully not a Eastern Hognose in your milk crate…I suggest having a good read of Freds guide:

http://www.mopedarmy.com/wiki/Fred%27s_Guide

As for the rear wheel yeah again like Will said check for play in your wheel bearings and that the wheel nuts are tight…see here for wheel bearing adjustment and greasing:

http://www.mopedarmy.com/wiki/Repacking_Cup_and_Cone_Bearings

Video of the hissing will help to…

Re: PLEASE HELP: Moby hissing and back wheel shakes on advance

It sounds like you need to check the starter clutch and main clutch pads for wear beyond limits.

« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account