11,500 miles and needs a rebuild.

[Nick89]

I'm an auto mechanic at a local shop. I do oil changes all the way to major engine work(rebuilds). My brother got a 2006 GS500F from one of our friends

Our friend knows nothing about bikes, The first time our friend changed the oil in this bike he used 2 cycle mixing oil for the motor oil. I caught this mistake and made him put normal oil in it but I have no idea how long he had the 2 stroke oil in it before I caught it. 


It runs but there is a lot of mechanical noise the idle is a little weak and I have a feeling the carbs need to be rebuilt and that it needs new bearings(con rods, mains, ect)

Its using 91 octane fuel but its pre detonating(pinging/knocking)

It back fires on start up and has a lot of trouble with the choke, it makes this hissing popping noise and loose's power for half a sec. All this when its warming up. Theres a tone of vibration also.

I want to tear the engine apart but I'm not sure if there are any special tools for this engine or in general that I need, It can't be any harder than a 8.0 litre V8 can it.    

If there is anyone with experience with doing this please dump it on me.

[dropitlow88]

this engine is a glorified lawn mower engine. tear until your heart is content. i rebuilt mine as a basket case with no prior knowledge (to this engine) easy as pie.

[Nick89]

That's good to hear, I just picked up the service manual 1990-2009.

Any special tools that I will need to buy?

[noiseguy]

Is the bike making rod knocking noises, or show low compression? If not, I think a teardown is premature. 2-stroke oil is just 10W... it's not great for the engine but I don't think it would immediately trash it either.

I'd start by cleaning out the carbs and checking the valve clearance... either of those could cause those issues. You'll need some thin gauges and a tool to hold down the buckets. And a carb synch, if you check that as well.

Check the exhaust gaskets as well... leaky gaskets can cause issues.

[dropitlow88]

other than the mentioned tools nothing special. i replaced crank and rods on mine without a manual. it's pretty simple. i just referenced the internet and this site for torque specs and timing procedures.