[jradd127]

I got an XR70 from one of my friends, bike was sitting on a stand & ran fine. Brought it home & throttle seemed to be sticking (every time I touched the throttle the bike seemed to stay in higher RPMs than it had been at before hitting the throttle). After dealing with a bunch of small problems I got the bike back together & running. The idle was really high & the idle screw & air/fuel screw didn't seem to effect the bike. I put it into gear & rode it around my house a few times. It ran fine on it's own but when I gave it throttle the bike died wanted to die out. Eventually it started to respond to throttle in first gear so maybe it was dying out because it was cold? Why's the bike idling so high? I'm gonna go play with the screws for a bit but I'm not sure exactly what it is. Ready to buy a new carb but not trying to add something else to the list of costs right now.

Any advice?
*Also bike was smoking a little bit, doesn't have brakes right now so when I put it into 2nd gear the only way i could slow down is by shifting back to first & the bike revved up & smoked more when I did that...could the throttle be pinched somewhere?

 

[jradd127]

I messed with it more & it's not as bad but air/fuel & idle still don't effect the bike and the idle is still too high

 

[mrjetskey]

Dis assemble carb clean ot jets low and high speed you'll need very small strand off a piece of 18 gauge copper wire (one strand only) to clean low speed jet then install an inline fuel filter . Those engines run even if piston and rings are worn and it smokes ,its carb for sure after cleaning set air screw at 1 turn out tune from there!! PS also the foam air filter inside the housing falls apart from the oil and the gas fumes (the petcock falls apart rubber) so inline filter is a must. A clogged air filter will cause plug fouling so does oil burning so change spark plug also (PS the petcock screen (on off valve) remove it from tank to clean it. I have done 3 crf 70s in last month all had same problems. one only had 4 hrs on it since new 2006 with 7 yr old fuel. JMHO.

 

[T Bolt USA]

Air leak or Clogged pilot

RUNNING CONDITION

Please got thru these steps:

Engine and Carb quick check list:
TBolt USA Tech Database - TBolt USA, LLC

To Check Valve lash (Tappet adjustment):
TBolt USA Tech Database - TBolt USA, LLC

Jetting guide:
TBolt USA Tech Database - TBolt USA, LLC