Any Resolution to Slow-Off-The-Line Problem

[demingr]

I have pretty bad hesitation/acceleration from a dead stop. It starts out the first second ok, then sort of trails off for a second, and then kicks in the third secod and continues to accelerate fine. But, that dip in acceleration/power right at the start is very dangerous.

I have seen some other posts about the problem, but has anyone had it resolved or know what the problem is?

Also, I'm about to take my 2006BR in for its 600 mile service. Anyone think that will fix it ? What can I expect from the valve tune-up etc?

thanks!

[Phil_R]

@ 600 miles the BR engine is probably not producing maximum HP... you will likely notice an improvement over the next 1000 miles.

Verify (check) tire pressure, 25 psi front, 33 psi rear... make certain brakes completely release.

Valve check / adjust may or may not result in noticeable improvement. Talk to tech, ask for idle-mix adjustment, but request adjust for max idle speed... do not perform 50 RPM drop adjustment. (If service dept. / tech / mechanic doesn't understand... you probably don't want them adjusting the valves either.)

If anyone suggests that if you can't hear the valves, they are OK and don't require adjustment... say thank-you, but no! Then find a mechanic willing to work on your BR, and doesn't mind doing a proper job.

Ask that oil is not overfilled... then check yourself before leaving shop. (demand removal of excess oil... it's not OK)

Accelerating from stop, CVT with auto-clutch: Engine idling, twist throttle, engine "spins" to 4000 RPM. As clutch fully engages, engine loses RPM. (completely normal scenario with auto-clutch) Engine recovers and holds 4000 RPM until CVT reaches the lowest numerical reduction... engine speed now increases with increased road speed. Sometimes what is perceived as an engine "bog" is simply a normal loss of engine RPM as the auto-clutch fully engages.

Does your BR match typical traffic acceleration... if so, it's probably about right. BR = 1 HP : 30 LBS (me riding my BR) Buell = 1 HP : 10 LBS (me riding my Buell) Most small automobiles are in the 1 HP : 30 LBS (HP : Weight) ratio. My BR accelerates like a small, fuel efficient automobile, not a Buell.

[demingr]

Thanks Phil, that was really helpful. I have now had my 600 mile service & valve adjust and it has help some. Your description of the CVT rpm drop-off and recovery seem consistent with what I'm seeing now. I'd still like it to be a bit more responsive/aggressive from a dead stop. I'm thinking about the roller replacement that tfazio has described & just ordered the service manual so I can get a little more familiar since I don't have much experience (I'm great taking things apart - no fear - its the getting them back together department I need help with) ;D

[Tony]

demingr said:

I have pretty bad hesitation/acceleration from a dead stop. It starts out the first second ok, then sort of trails off for a second, and then kicks in the third secod and continues to accelerate fine. But, that dip in acceleration/power right at the start is very dangerous.

I have seen some other posts about the problem, but has anyone had it resolved or know what the problem is?

Also, I'm about to take my 2006BR in for its 600 mile service. Anyone think that will fix it ? What can I expect from the valve tune-up etc?

thanks!

1 - Put 6 16g rollers in the variator
2 - upgrade variator to Malossi or Daytona
3 - around town only? use a Red Daytona Contra Spring
4 - decent all around use a white malossi Contra Spring
5 - Adjust the valves - and this may need a slight tweak from the factory procedure.
6 - look at the oil level also like everyone says
7 - i have good luck with an iridium spark plug
8 - the drive belt will break in also and improve low end acceleration also.
9 - email me direct [e-mail]

[chanito]

Thanks Tony and
We always appreciate a technical mind ;D ;D

[tfazio1]

ok now someone find me a Replacement adjustable rear shock

[tedsmini]

At my first oil change I went to Amsoil sythetic. I only had the sear of my pants to judge but the lag was much reduced as the engie spooled up faster. By 1000 miles the speed and acceleraton of the bike was markedly improved: hang in there it's a fun scooter.