just discovered the scorpion exhaust isnt for my vfr 400 its from a cbr 600

im thinking its the cause of my hesitation when fully opening the throttle low down

opinions?

I doubt it.

It's more likely that the pilot screws on your carbs haven't been adjusted properly to match the exhaust. This will cause the symptoms you describe. Balancing the carbs can also help.

You can tune the carbs to suit virtually any type of exhaust system, let alone different mufflers.

is tuning the carbs easy? or am i best sticking it in a garage

leerc wrote:is tuning the carbs easy? or am i best sticking it in a garage

It's not difficult, but it can take a fair whack of time first time around - labour/time is what the garage will mostly charge for.

You need to know what your pilot screw settings are currently set at. I think you can get a screwdriver in there to check with the carbs on the bike (I've never tried), but it's much easier with the carbs off the bike, that's where the time is.

If you do it yourself:
- Tighten the pilot screws until they're just nipped up (not too tight), write the result down on paper for each cylinder (to the nearest 1/4 turn) and post this up
- A good starting point would be to then open them 2.25 turns out (count each 1/4 turn you do)
- See if that performs any better and get back to us

It's fairly common for these to be not properly adjusted.

hopefully ill be able to get in without removing them

if the winds died down ill get stuck in at the weekend

is it a case of making sure all 4 are set the same or does each carb need fine tuning ?

leerc wrote:is it a case of making sure all 4 are set the same or does each carb need fine tuning ?

All the same is more than enough

If you'd like to buy a special device called a CarbTune we're having a group buy in January

iDemonix wrote:If you'd like to buy a special device called a CarbTune we're having a group buy in January

Carb tune also do a very very very very useful 90deg screwdriver, this tool alone will save you hours and hours, well worth the £50, and if you are going to work on your carbs (balance or tune them) over the winter each year it's well worth the money.

can they be done with the carbs on with that90 degree screwdriver?