www.gpz-305.de

Rey · Verfasst am: Do Jan 10, 2008 6:28 pm Titel: 305 running to fast

hi i am refurbishing a gpz305 and i have got the engine running but have one problem the engine will start after a while and then rev to over 4000rpm and stay around there when i put my hands over the carbs it then raises the rpm.
if i remove the vacume ports the engine still runs around 4000rpm
if i apply choke the engine picks up rpm aswell

what do you think could be wrong with the bike could some one write a list of things to check thanks
the bike had been stood for a while and has 23000 on the clock wb thanks
if any one has a working carb that they want to sell to c if it solves the problem leave a post thanks

Lothi · Verfasst am: Sa Jan 12, 2008 9:04 am Titel:

Hi Rey

Maby carbs are out of sync

First clean them:

http://www.gpz-305.de/English/Tips/Carbs.html

After make a rough check :

Unscrew one spark and put it back into the plug, so it has contact to the body and CDI is protected against overvoltage
(never start engine with no spark in the spark-plug and contact to the frame !)

Then start the engine, now running with one cylinder.

Now do the same thing with the other cylinder.

Rpm has t o be equal, otherwise the carbs are out of sync or maybe some other failure (air lakage, low compression etc.)

Btw: If You remove the vaccum-ports, the rpm will rise due to excessive "leakage"-air bypassing the normal way !

My suspicion is that there is some air-leakage; air bypassing teh carb-system.

You can check also this by having the egine run and spraying with start-pilot (or a fuel-soaked sock) around the carb and the black rubber-made rings where the carbs are fitted to the engine: rpm should not change by doing so !
_________________
Grüsse

Lothi tach