TGB 101R starter failure

[sajtqkac]

Hi,

I need some help with my TGB 101R scooter.
The carburetor is clean, everything is good with the scooter except that it
won't start by the starter, only by kickstart. I used a stroboscope to check
the ignition and there is only spark when I kickstart the engine, no spark
when trying to start it by the starter motor. CDI is okay, I replaced it
with a brand new one, starter motor's relay works fine, looks like there is
no damage to the wires and all connectors are clean and connected.
Nobody ever took the magneto apart, the original factory mark is still on the nut.
Do you have any idea what to check? Thanks for your help!

Peter from Hungary

[harry]

welcome Peter ,
sounds like it might be a faulty  brake switch , try holding in the right one ,
maybe check that its (left )connected

the switch has a electric connection to the CDI  and will
not allow the power (ground ) to complete the starting circuit.

there are links to the service manuals at the bottom of the forum homepage
it also has  the wiring diagrams .

oilyhans

[sajtqkac]

Hi Harry,

Thanks for your help, but still nothing. Brake switches are okay, both switch is working. Today I took apart the starter motor and it runs fine, no damage to the brushes, it spins easily. I've found the circuit drawings in the service manual but it's quality is unreadable. It would be great to make the starter working.
Today I tried to feed the scooter with a 12V car battery, but still doesn't wanna start. There is 12.3V in the battery on styndby, and 11:8V when using the starter, no reason why there is no ignition... Please help

[harry]

so the starter  doesn't turn over when in the scooter?
 there is a starter relay ,follow the red battery wire to the relay.
try bypassing it .   also nothing will work if the fuse is blown ,you might check that .

if it kick starts the coil and cdi are good....

 oilyhans

[sajtqkac]

The CB is okay, the starter motor spins the engine perfectly with the speed it needs to be spinned but there is no ignition. I have no idea whats wrong. I'm sure that its very simple but we have to figure it out. I saw on the circuit drawing that the rectifier is also part of the ignition circuit but I think it works fine.

[harry]

have you checked for spark?

oilyhans

[sajtqkac]

Hi,

I've found the problem today. The ignition coil is wrong. It doesn't generate strong enough spark on lower rpms around idle. I replaced it with a new one and the scooter is now working fine. Thanks for helping me.