1989 GSX-R250 (GJ72a) starting problems

[quickshotnz]

Hi Guys,
Its another dreaded post about a GSXR250 (GJ72A)

So brought this bike a year ago running. lasted 2 weeks then decided it didnt have enough compression anymore.
Ended up buying a second hand motor with much lower kms (suposed runner) to replace the tired engine

Finally get bike all back together and when i try to start it, all i get is clicking from the starter relay and sometimes it trys to turn over a lil bit.

New battery - still wont start
New starter relay - still wont start
New high amperage wires from battery to starter relay and starter, and got the starter tested at local autosparky - still wont start

battery sits at 12.7volt then when i try to crank it goes straight down to 8v
Thinking there is a crook wire somewhere that is shorting out?

I have checked all the kill switchs (engine kill switch, side stand, neutral switch) and they all work fine.


Any ideas or help would be greatly appreciated, as this is driving me nuts lol

Cheers
Sam

[spanner spinner]

the most likley place the short can be if the battery is pulling down to 8v is in startermotor circuit. If the short was in any of the other wiring the smoke would have escaped by now as the wirings not heavy enough to carry that type of current for long. Three things to check, the solenoid check that it is not shorting to earth when activated, the startermotor check it's operation that the motor doesn't have a internal short on the armature, and the engine it's self as a seized engine usually pulls a battery down to the 8v range.

[Akzle]

turn motor over by hand to check for seizage. Fill the cyl with oil overnight beforehand.

As above, check for shorts to ground. I'd expect somewhere on the hot wire downstream of the switch has rubbed through.

Try starting it with a flying hotlead.

[Akzle]

are you sure it's the relay clicking, not the solenoid?

[jellywrestler]

did you put the main earth back on proper?

[Askor]

Swap the starter motors over

[Akzle]

did you put the main earth back on proper?

was my thought, but couldnt short to ground if it werent.

[quickshotnz]

thanks everybody for your suggestions,
have solved the cranking issue.
i was having clearance issue with the generator crankcase cover.
i have fitted a thicker gasket and the engine is now turning over flawlessly.

Now chasing the spark gremlins lol

going to swap over signal generator tommorow hopefully i get consistent spark

cheers