Bogging off the line

[GSJimbo]

took the gs to the strip yesterday and had a bog off the line, hit the two step and let it fly and right about 15 feet out it bogged, could it be a float problem (low on gas) or a needle setting (to lean), felt like it ran out of gas for a second then caught and ran great down the track...help!! running 36 flat slides Mikunis.......thanxx

[KGB]

Do you use an in line fuel filter?
if so get rid of it........it's starving the motor

[GSJimbo]

no,a Pingel petcock........

[spyderrocs]

im having the same problem sorta. Mine just has no good acceleration until midrange. I pulled the carb apart and their really dirty so you might want to try that. is your choke stuck on?

[rosco15]

Are you running a lockup style clutch. And your popping the clutch out dragbike style? if so then it's too much static spring pressure. If it's like mine it will leave the line and then wallow around as the clutch pulls the motor down. Also check where your 2-step switch comes on and off. It should come off just as the clutch starts to drag. You can set it in the pits.

How did it run?

[GSJimbo]

it has a lockup clutch with no washers just the nut and bolt, it had one washer and took that out and was a little better, when it bogs I just can't back off the throttle and grab a handful again it takes a little while to catch....it ran a 11.30 I know I lost a second or more monkeying around with the bog,, just after i took it off the trailer turned the gas on and gas poured out the over flows, so something might be going on there floats were sticking. Thanks all

[RacingJake]

Also what rpm do you have the 2step at ? Go up another 1K and see if that helps. Sometimes it's just easier to drop or raise your launch rpm due to track conditions. I hate being one of the first 20 runs of the day since the track gets better later on.

[lecroy]

took the gs to the strip yesterday and had a bog off the line, hit the two step and let it fly and right about 15 feet out it bogged, could it be a float problem (low on gas) or a needle setting (to lean), felt like it ran out of gas for a second then caught and ran great down the track...help!! running 36 flat slides Mikunis.......thanxx

Without seeing the bike run its hard to say. If the engine is running right then I would point my finger at the clutch setup. You may just not make enough power. Playing with the little RD any trying to make it not bog gave me a real good hands on test of trying to make something with little power not nose dive.

If it is the clutch, I agree with Ryan to a point. IMO, its a balance act of static, dynamic force plus power, tire size, tire pressure, RPM and a million other things you can play with. Then there are the million things you can't control like track prep. From my experince (keep in mind I am new to this whole lockup thing) the static effects the initial few feet. By 15 feet, the weight from the arms should really be kicking in. Say you start with 200 pounds of static (which seems to be the number that everyone throws out), if a nut and a bolt weighs 10 grams, once clutch is locked and the engine is spinning at 3000 RPM, there is an additional 50 pounds of force on the pack. At 8000 RPM, the force goes to 250 pounds, added to the 200 static for a total of 450 pounds. So, you can see that a lot of weight on the arms can really play a big part in draging the engine to its knees.

I agree with Jake, it's easy to change and can have a major effect on the launch, assuming there is nothing wrong with the engine.

But if your floats are sticking, you have other issues to dig into before you play with the clutch and all the other things you can tune.

Have fun with it.

[GSJimbo]

had the two step set at 7800 and lowered it to 7600 and it seemed to help a little....I'll keep at it......

[lecroy]

Up, meaning try 8000, not down.

[GSJimbo]

I found out two things I did turn up the two step from 7600 to 7800 (not like I said) and it helped a little and adjusted the clutch to the two step and found the clutch was releaseing before the two step did, Got the two together, next week going to adjust the carb floats,and take her to the strip and try it out...thanks all

[lecroy]

... adjusted the clutch to the two step and found the clutch was releaseing before the two step did ...

This is not good. It should make a difference.