7 replies to this topic

[mjc477]

hi i have a 1976 tl125 with 150 kit on it

it did run like a watch only a fortnight ago
i went to start it the other night and it has completely lost its spark at the points

it is in of road trim so only has a generator,coil, points and coil

i disconnected the kill switch

no spark

changed plug plus plug cap

no spark

got my multi meter out on all cables
all had continuity

is this a common problem and does anyone know the next sensible place check

there is next to no wiring on this bike so it surely must be a component failure

cheers
guys
jason

Edited by mjc477, 03 September 2010 - 04:59 PM.

[TLTEL]

Hi Jason
I have the same bike and in the past have had similar problems.
I cant remember if there is an earth for the coil but if there is, check and clean this first.
It is more than likely to be the points that are causing the problem, I ve never had a problem with generators or coils.
Check that the points are clean and definately closing and opening, turn over by hand. Check for a frayed wire on points conection a single strand of wire touching the engine will stop it sparking.( I have had this happen and its not obvious at first glance)
If that is all ok could be condenser but you will usually get a lot of arcing at the points.
Finally check for up and down movement on the cam shaft, if its got movement it will alter ponts gap when it is spinnig.
Hope this helps.
TLTEL

[mjc477]

cheers for that i will check points tomorrow for bad connection and damaged wire

i dont think its the condensor as i have had problems with them on an old vw camper and it was eating points weekly

the points are like new if not indeed new ones fitted
thanks

[TLrider]

Check the condensor wire at the coil. Mine broke there once and I had no spark.

[mjc477]

TLrider, on Sep 3 2010, 09:40 PM, said:

Check the condensor wire at the coil. Mine broke there once and I had no spark.

hi this morning i checked the points and found a very poor connection on the points lead crimp so i solderd it up

i had a great spark!!!!!!

i put a few things back on i had of and it ran for about 20 seconds very iraticaly then pop and it stopped obviously the last spark on some unspent fuel

now i have no spark again

i think now i will change the points and possibly the coil and condensor £20 ish i would imagine

this should illiminate any old corrosion on more electrical connections i cannot acess

does this make sense or am i just hopeing

cheers
agian jason

[TLTEL]

Hi Jason
Still sounds like the points area is where you will find the priblem.
The wire that runs into the points through the rubber grommet could be at fault, if its an original wire, change it as they become brittle.
When you screw the points cover on it could be shorting out.
Try startimg it without the cover on and see if its any different.
good luck
TLTEL

[mjc477]

TLTEL, on Sep 4 2010, 06:57 PM, said:

Hi Jason
Still sounds like the points area is where you will find the priblem.
The wire that runs into the points through the rubber grommet could be at fault, if its an original wire, change it as they become brittle.
When you screw the points cover on it could be shorting out.
Try startimg it without the cover on and see if its any different.
good luck
TLTEL

hi i have had the cover off and have checked cable with multi meter and it is fine
i did rewire the cable anyway but still no difference

i have rewired all other cables now

generator-points
points- coil
still no spark

i will get new points anyway now

i have also buzzed out the circuits and i have a dead short to ground on the generator windings this does not seem right to me????

thanks again

[mjc477]

TLTEL, on Sep 4 2010, 06:57 PM, said:

Hi Jason
Still sounds like the points area is where you will find the priblem.
The wire that runs into the points through the rubber grommet could be at fault, if its an original wire, change it as they become brittle.
When you screw the points cover on it could be shorting out.
Try startimg it without the cover on and see if its any different.
good luck
TLTEL

hi tltel
thanks for all your imput

i have just come back from the garage smelling of exhust fumes as its now running....

what i found was the wire connecting onto the points was connected on the wrong side the correct order is

The order from left to right should be - bolt, upper ignition point metal band (upper point contact is on this band), b/w wire attachment, insulator, contact point housing (the actual metal piece that attaches it to the backing plate), insulator, washer, lock washer and nut.

mine was connected on the wrong side of the mounting plate it still did have a circuit all be it thru a load of connections

i connected the crimp straight onto the metal band of the top point and their it was a nice thick spark.......

it had run like that for ages and now it had given up


cheers again for your time

jason