Most motorcycle problems are caused by the nut that connects the handlebars to the saddle.

My "New to me" CB500

NFortySeven
NFortySeven
Squiddy
Squiddy

Posts : 11

My "New to me" CB500 Empty My "New to me" CB500

Post by NFortySeven on Tue 14 May 2019, 12:39 pm

Afternoon all!

I bought my first bike a couple of weeks ago, never heard of the CB500 before this one came up at a bargain locally.  It's a '94 CB500R with 35k from new, partial service history, 2 keys and 2 original owners cards.  Story is, the previous owner accepted as a trade-in at the motorcycle dealership he works at and had planned to turn it into a cafe racer, he then loaned it to his friend for a couple of weeks last year, but it just laid up in his friends yard until a couple of weeks ago.

Here she is in all her glory:

My "New to me" CB500 Img_6811

My "New to me" CB500 Img_6810

I bought it knowing that it was going to be a project, and a labour of love as the bike is a non-starter.  The bike was fully serviced before it laid up last year, which included a battery, plugs, oil, fork seals etc. 

Originally when I got it home the bike was dead, not even click when engaging the start button.  I took a gamble and bought an oximizer for the battery just incase it could be recovered - and according to that it's fine and holds charge, I then changed the fuses in the started solenoid which were rusted, drained the tank and carbs of old fuel and replaced with new, got rid of any crud on the side stand and clutch switch connections.  Now the bike will turn over slowly 3 times, pause for a couple of seconds, turn over once, pause for a couple more seconds, and the turn over 3 times again etc.  I've tried rocking the bike back and forth in 2nd gear aswell to try and loosen the starter, but still won't fire up.  I thought it may be caused by the battery not supplying enough power, as it was only turn the bike over if it's above 12.5V, any lower than that and I just get a click.  Would a new battery be worth picking up?  I've yet to check the plugs, so wouldn't rule those out yet either.

Any advice is much appreciated!  Also, if this is in the wrong section please feel free to move.
NFortySeven
NFortySeven
Squiddy
Squiddy

Posts : 11

My "New to me" CB500 Empty Re: My "New to me" CB500

Post by NFortySeven on Tue 14 May 2019, 1:37 pm

Update!

Got the battery up to 13.9V and the bike started!

Idling around 2.5k, revved it up to 4k but it took a while to return to 2.5k.  Shut the bike off after letting it run for a few mins and then started it again, no revs but it is now idling at 4k.

Possible vacuum leak?
wrighty
wrighty
Three's a Charm
Three's a Charm

Posts : 141
Location : Market Deeping Lincs

My "New to me" CB500 Empty Re: My "New to me" CB500

Post by wrighty on Tue 14 May 2019, 6:24 pm

Check carb mounting rubbers for air leaks between carbs and head. It happened to me years ago on my mz. When i shut throttle it kept going at full revs, when i turned ignition off it still revved at full revs. I put it in 2nd gear and dumped the clutch to stall it. This was a race day at cadwell park and the spectators looking on thought it was highly amusing. When i eventually pushed it up the hill to the paddock i got a big cheer. Anyway  the carb rubber had a huge split and it was sucking fuel through regardless of my efforts. I guess even a small air leak affects carburation.
NFortySeven
NFortySeven
Squiddy
Squiddy

Posts : 11

My "New to me" CB500 Empty Re: My "New to me" CB500

Post by NFortySeven on Tue 14 May 2019, 7:01 pm

@wrighty wrote:Check carb mounting rubbers for air leaks between carbs and head. It happened to me years ago on my mz. When i shut throttle it kept going at full revs, when i turned ignition off it still revved at full revs. I put it in 2nd gear and dumped the clutch to stall it. This was a race day at cadwell park and the spectators looking on thought it was highly amusing. When i eventually pushed it up the hill to the paddock i got a big cheer. Anyway  the carb rubber had a huge split and it was sucking fuel through regardless of my efforts. I guess even a small air leak affects carburation.

Hmm, I could switch my ignition off and that would kill the engine, just when it was running the RPM would come down slowly after revving it, and then when it restarted it wouldn't go down below 4k RPM.  I will definitely check the mounting rubbers though!

Left the bike alone for a few hours and it no longer starts, even with the battery charged above 14V.  I get maybe 2 or 3 attempts to get it firing up before the battery's voltage falls too low to turn the engine over.  Half tempted just to throw it up to my mechanic and have him get it running, maybe this isn't my forte!
Jameshambleton
Jameshambleton
Moderator
Moderator

Posts : 2953
Location : Bedale, North Yorkshire

My "New to me" CB500 Empty Re: My "New to me" CB500

Post by Jameshambleton on Wed 15 May 2019, 6:44 pm

stuck choke /choke cable

Sponsored content

My "New to me" CB500 Empty Re: My "New to me" CB500

Post by Sponsored content


    Current date/time is Mon 27 May 2019, 6:23 am