Hey everyone,

I ride a Suzuki DR200SE year 2003. The bike was running great even at 110km/h. I replaced the carburetor because the membrane was broken, not the official Suzuki carburetor, but still the engine worked alright afterwards. Then one week later, a valve inside the cylinder broke, so the piston hit the sparkplug and got all melt. So I went to several mechanics who fixed the inner surface of the cylinder and replaced the piston and valves. That was all done by very ambitious, but not very well equipped mechanics, and I dont know about their knowledge. They had to work in nighttime with very less light, so I wouldnt wonder if something is not working properly as these two mechanics had to open and rebuild together everything under hard conditions.
So then after these fixes, I started running slowly for 500km because the piston was new.


But now as I tried to ride a little bit faster, a problem occurs:

When I go faster than around 80km/h, the engine seems to starve. It feels like there is a lack of oxygen or fuel, like the composition is wrong. It continues to "starve" down to 50km/h and needs around 10 seconds to work properly up to 80km/h again.
Also, I have to drive with an open choke, as the engine always stops running when I switch to the lower gears. I tried to close the choke when I'm riding in 5th gear at around 80km/h, but the starving problem still occurs.

I don't know much about the mechanics, as I'm very new to the world of riding.

Does anyone of you have an idea what the problem could be, or where it comes from?

Greetings,
Tobi

Where are you? Sounds like you need to source out a decent mechanic. If you let us know what country your in maybe someone can help. I don't know much about mechanics but would say s problem of that magnitude would be hard to diagnose over the web, though I may be wrong (I usually am on mechanical matters!) from what you say, sounds like the carb isn't doing its job properly. Maybe the air/fuel mix was so lean that's what caused the engine damage (too lean = too hot often translating to catastrophic engine damage). Any chance of sourcing a stock carb? I'd be wary of riding it especially at speed in case of further damage until you diagnose the problem.

LIke all folks, i say
"find a GOOD mechanic on BIKES"
It sounds like the " ambitious" guys did not put the GENUINE parts on your biek, so no ' easy) way to check up the problem. Might be
- the carburetor thatd does not fit the rest or doesnt work properly
- the removal and fixing back of the piston ( O rings ? )
- the fitting of valves afterwards
....
This GOOD mechanic should test every part . that's a job !
for me this
"I have to drive with an open choke, as the engine always stops running when I switch to the lower gears."
is like a carburetor fixing problem ( especially a membrane)
NOT SURE but check this first

It does sound like it could be a carb or fuelling problem. A few things you could check:
- As mentined before,is the carb attached properly? Is the carb fitted into the rubber inlet manifold. Are the manifold bolts tight?
- Hold the bottom of carb and try to move it side to side - gently.
- Are there any fuel leaks from carb
- is the throttle working well, opening the carb slide/butterfly fully?
- remove spark plug and check colour. Black will indicate mixture too rich
- is the air filter clean and fitted correctly. Easy job to remove side cover to access filter.

Engine
How does the engine sound? Any strange rattles or metallic noises.
Any oil leaks around the head gasket? Or hissing sounds of air escaping
It would be worth checking the valve clearance again.

[Edit]: Does the carb have a "rev limiter" switch? Activated when the throttle is fully open.

thanks for all your input! As it really was unclear whats the problem I went to a recommended mechanic in Barranquilla, Colombia. He took himself 3 days and changed the camshaft as it was really used off. There was no adjustment on the carburetor, but now, after getting a new camshaft and rebuild and resynchronize everything again, the engine works fine again! So Im not totally sure wether it was the camshaft or the synchronisation, but Im happy its working again

P.s. youre totally right, you should meet a good mechanic if possible. Unfotunately, I was in the nowhere in Nicaragua and this mechanic was my only possibility, as I was in a rush to get a boat in Panama, too.

Hey,
unfortunately, the problem occured again to me yesterday and today. Starving engine at 80km/h followed by explosions in the exhauster when I slowed down. also, the engine died and was able to be restarted first after 15 seconds.

Im going to check the valve clearance again. But why would it change again? i mean i have driven around 3300km since the last synchronisation, not more. what could cause the valve clearance to become THAT bad (i mean really symptomatical) AGAIN? Its hard to explain my problem to you guys in english, but even a lot harder to explain in spanish to the mechanics. Im near Trujillo in Peru now.

Hey Tobi,

schreib mir mal eine e-mail, damit ich deine Adresse habe (ungemein@gmx.de). Sind auf dem Weg nach Peru.

Viele Gruesse Dennis

P.S. wir haben uns in Macas getroffen.