Dr125 running issues

[hmmmnz]

Hi guys. I bought a little Suzuki Dr125 same motor as (gs. Gn, gz. En125 and quite a few chinky copies)

Any way bought the bike as a wee project.
Basically it's running with a bit of a hiccup at full noise and generally underpowered. And barely does 50 on the clocks

I did the valve clearances which were non existent. So thought it might have a burnt out valve. But a co.expression test disproves this at 110psi with and with out oil in the cylinder.

Starts easily. Idles fine. But sometimes dies at idle when hot (easily starts again)
The revs hang a wee bit. But doesn't have any air leaks.

Plug chop seems to be good.
Carb has been cleaned.

Any clues as to where I should be looking for a problem.

Mucho thanks
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Suntan Sid]

Is the air box standard or has some gimp drilled holes in it for more "powahz", are all the bits there, including the seal around the lid, or where ever it opens?
Is the filter good?
____________________
"Everybody needs money, that's why they call it money!"

[hmmmnz]

yeah all bits are there, and all standard,
air filter was replaced with another oem item.

seems to be a bog standard bike that just needed a tidy up
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Suntan Sid]

Could try the HT lead, check for cracks, chop a bit off the ends and make new connections.
____________________
"Everybody needs money, that's why they call it money!"

[hmmmnz]

Thought the same. So had ordered a new coil, lead, plug and cap earlier today.
See if that makes any difference when it turns up.
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Rogerborg]

I test rode two, a 2008 and a 2011 (same owner, no idea why he had two). They were both identically dull, gutless and sluggish and just didn't want to rev - and that's by my standards.

They weren't missing though, so it sounds like something is up with yours, but I wouldn't expect miracles.
____________________
Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[hmmmnz]

for sure, they are strangled, the exhaust header has a reducing tube in it, which wouldnt helping, the cam seems very dull as well, very short duration and minimal lift,
i think even the carbs are smaller than the gs and en bikes

i went for a ride on it with the mrs little brother he was on a sinnis cafe 125, it has the same motor, and i wasnt even close to keeping up.
its more like a tuned 50cc than a 125 (even if it is a 4 stroke it should be a bit faster)
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches