Plug chops at Loudon

[SilverDragon]

Ok so my RS125 runs great. BUT I'm still only close on the jetting. What do you guys do for plug chops at Loudon? Keep it in first around T11, kill it and pit in? Or do you guys go the nascar T1 after holding it open on the straight? jk! I bet they'd frown on the whole wrenching on the bike on track.. lol

[Paul_E_D]

Plug chops need to be done in at least 4th gear, so there's really nowhere to do them at Loudon except MAYBE the T10-11 straight and coast it in, but you'd better make sure noone is behind you...

[Ken C]

How about shutting off at the end of the staight and going around the oval? Stop at the wall and push it through the T1a gate after practice is over??

[McBiggity]

can someone explain what a "Plug Chop" is to me?

[Doc]

Originally posted by McBiggity
can someone explain what a "Plug Chop" is to me?

[Ken C]

It's how you read how the fuel/air mixture is by looking at a spark plug at the point where it's at top rpm. It's commonly used when tuning two-stroke motors where the jetting needs to be spot-on. If you were to idle into the garage and then check your plugs, you'd be reading how the motor runs at idle- not helpful.

[Doc]

OK I have learned my one new thing for the day, time for a nap.

[Paul_E_D]

You can't do them on the straight. It's just too dangerous. Someone could be passing, or following close and target fixate etc. Bikes going different ways is no good...

[Evil_Weasel]

well i guess you'll just have to sneak out back to one of the parking lots.

[Paul_E_D]

You can't "sneak" anywhere on a 125!!! 104 decibels of ring ding will alert anyone within a mile of your presence. Ask me how I know

It'd be nuts to hit the top of fourth in a parking lot out back...

The real solution is the T10-11 thing, plus reading the piston top and plug together... As long as you don't trundle around the pits to much, this will be accurate enough to get within a jet or two. Then you can go by feel/revs

[TTD]

Back when the AMA used to race at Loudon, there was a 250GP race and we were allowed to do plug chops down the front straight at the end of practice.

They would even have Golf Carts come and "pick us up" and give us a tow back in.

It was pretty cool to see a line of 250's parked around the top of the Turn 1 oval waiting.

My first one really freaked me out. You're doing a buck something in full tuck at wide open throttle ... then you pull in the clutch and kill the motor... and purposely miss the corner.

You go from lots of noise from the motor... and lots of acceleration.... to NOTHINGNESS.

It's amazing how loud everything else on the bike sounds when the motor is off.