additional probs dt200 wont rev out

[twinrock]

Ok so bike is up and all running engine sounds pretty good and healthy.how ever it can be hard to start and only will start with choke on..fires, runs slightly dies.. repeat but runs a lil more each time..then runs on choke then good..sits and idles nicely and turn it off it starts easily.. next day same situation..may take 5 or more kicks befor initial fire..secondly the bike lacks power mid and no top..will only rev till about 7500 rpm..even wih power valves locked open..just seems way down on power compared to anyothr dt200 I have ridden..bottom is fine..but after 5000rpm power flattens off and tapers out..the bike has had the snorkle removed from air box and 2x25mm holes drilled in the side of air box I under stand standard jetting is
Pilot 35
Needle second clip from to
Main 170
Float hight...??
Cant imagine mods to air box leaning out by that much..plug still looks brown I went to 185 main..but made no diffrence.. but def feels restricted..clogged exhaust? Float hight?any info would be great thanks

[JonW]

sounds like it needs a rebore, they act like this when needing one.

[twinrock]

Yeah well I have thought of that..lucky me never really owned a floged out engine to know what one feels like..they are either fresh or seized..lol

[JonW]

lol, well yeah... I bought one that i knew needed a rebore and it responded well to that, but before that it was a bugger to start. Once it was started it was fine, a combination of oil in the rings and heat helping the piston seal better. once bored it was a corker... piston, gaskets, bore... few hundy there

[twinrock]

Yeah im a fan of the dt200..but really dont feel like rebuilding it..

[EPApolice]

I can tell you from experience my bike did the same and someone had drilled the airbox also, I taped the holes up and a perfect running bike was the result, I'm talking day and night difference. Obviously the DT is sensitive like that. I think from memory 145 main is standard. It may well be flogged out too but I would cover those holes first and see.

[JonW]

Good thought on the holes Pat, IIRC these carbs dont have an airscrew and so you cant tune it to run with more air :/

[twinrock]

I will try that tomorrow.The engine does sound very tight thats why I bought it..and smooth..bottom end is great..cross fingers hopefully I can reverse whats been done.. pat was yours missing the snorkle also.?

[EPApolice]

I cant remember but I think it was still fitted just some holes drilled and a larger main. I put a pro circuit can on mine a few months back that is correct for the DT, sounds great and feels a bit stronger too. I didn't need to change anything with the jetting.

[twinrock]

Well I blocked the holes and put a 160 main in it..just to be safe..took it for a run..it was better..I got a snorkel to pic up tomorrow..then ill go back to 145 main it also has a pro circuit muffler so good to know I wont have to mess with jetting..what setting is the clip at from factory

[EPApolice]

No idea what the clip position should be.