new heart for my bike

[ben111]

hi all,

i've been here before to check out all the project topics because i was pimping my bike a little bit some time ago

loved to see how a gs 500 could be modded.

this was my bike



a little blurry but was taken with sellphone some time ago.
i loved riding it untill i blew up my engine. i've bought a second hand one, it broke down 3 weeks later.
i've bought a second second hand engine, it never worked...

i would love to ride it again and mod it a little more so i was searching recently and found an old gs 500 for sale.
the owner said to me that the bike is fine but it was standing stil for a long time and the enginge runs but fails when warming up.
he stated that it was a carburator problem.

i have 2 pair of carbs here in my garage so i'm tempted to buy it.
i asked for a better explaination for the problem and this is what he said (trying to translate as good as i can)

"the last time i tryed, the bike started easely, but couldn't almost give any gas (throttle)
when you give to much gas, the engine stoped, only if u do it really slowly, it goes up in rpm allthough it doesn't want to go over 4000-5000 rpm.
when the motor is warm, it shuts down and i have to wait again for it to cool off to start it again"

does this seem like a broke carburator problem? or badly tweaked carbs?

i know that here are a lot of pro gs 500 people so i'm hopeng to find my answer here so i can ride again in the summer.

thx in advance

Ben

[Andy13186]

damn howd you blow the engine?  nice looking bike though

i dont know much about the engines just curious to what happend to yours

[ben111]

well, i was running a bit late for an apointment so i was stepping on it, and as i was passing by a few lorrys, there came an other car from the other direction so i really had to go high in rpm to make it. i remember seeing the little light of the oil turning on for about 2 seconds and bam, a realy lood rattling sound.

the enigne still ran, but in the inside it was all messed up.
such a shame, bought a cbr 600 afterwards wich i've sold a year ago so i realy want this want to ride again.
i knew an aircooled 2cilinder bike like a gs 500 was sensitive for lack of oil but i didn't know it would go that fast, guess the oil wasent thin enough at the time i went so high in rpm

[BaltimoreGS]

Sounds like a probable carb issue, check to make sure both exhaust pipes are getting hot.  It would be a good idea to run a compression test too if he'll let you.  Would be worth the risk to me if the price was low enough.  Good luck!

-Jessie

[tt_four]

That's a very clean looking GS. Did you ever have troubles with your tire hitting that undertail?

[gregvhen]

That's a very clean looking GS. Did you ever have troubles with your tire hitting that undertail?

+1 or did you raise the subframe a little bit?

[ben111]

he asks 475 € and that's his last offer. that's for the whole bike.

how can i do a compressiontest, unless i would drive it to a bikeshop?

and for the people who asked, the undertail was bend a little bit and i replaced the dogbones with custom made smaller dogbones, just a few mm shorter and it pushes the bikes tail up for 3-4 cm.

driving with a passenger is impossible but alone is fine. i've hit the untertail 2 or 3 times but that was because i took a real deep whole in the asphalt.

people who also have an opinion about the carbs, fire away!!

[tt_four]

You can go to the auto parts store and get a compression gauge for $20, when take a spark plug socket and the tester with you to check out the bike. You just pull out the plug, put in the gauge, twist the throttle and hit the starter.

[ben111]

You can go to the auto parts store and get a compression gauge for $20, when take a spark plug socket and the tester with you to check out the bike. You just pull out the plug, put in the gauge, twist the throttle and hit the starter.

but if i twist the throttle, the engine turns off like stated in previous posts

[tt_four]

The bike doesn't need to start to test the compression, it just needs to try and start. If you're not getting any kind of reading with the throttle open, just try it without the throttle. Even if you can't tell exactly high the compression is, it'll at least give you an idea if anything's wrong with it.

[BaltimoreGS]

You can go to the auto parts store and get a compression gauge for $20, when take a spark plug socket and the tester with you to check out the bike. You just pull out the plug, put in the gauge, twist the throttle and hit the starter.

but if i twist the throttle, the engine turns off like stated in previous posts

You don't start the engine on a compression test.  First let the engine idle until it heats up.  Then you remove both spark plugs, attach the compression gauge to one of the spark plug holes, hold the throttle wide open to allow maximum air flow, crank the engine with the starter about 10 seconds (or until the gauge quits going higher).  Then repeat on the other cylinder.  The 2 readings should be within 10% of each other  (140-150 psi is a good reading).  If one cylinder is significantly lower than the other add a few teaspoons of oil into the spark plug hole.  If the reading comes up then you have a ring problem.  Hope that makes sense   

-Jessie

[ben111]

hi guys, just wanted to let you fellas knopw i didn't buy the bike afterall.
it was in my opinion a bit to much money for a bike who had a bit to much work to be done.

still looking for an other offer to come buy and hope to ride again soon

thx to all for the help!

[dauphinc]

Good looking bike. But yeah sounds like an ignition problem actually..i see it alot at work.