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Hi,
Ever since purchasing my 2001 falco in sept last year it's had a hesitation period from 2,500k to 5,500-6000k rpm, it feels like it's shaking, after 6000k it pulls better!
I've checked the TPS sensor and it's bang on!
Another thing I noticed was that there was a small amount of oil in the airbox and the throttle bodies seemed quite dirty!
My thoughts are balance and clean the injectors, not sure how to clean the injectors properly, I assume the balancing is done the same way as with carbs with vacuum gauges?
Any ideas?

Yellowperil wrote:Hi,
Ever since purchasing my 2001 falco in sept last year it's had a hesitation period from 2,500k to 5,500-6000k rpm, it feels like it's shaking, after 6000k it pulls better!
I've checked the TPS sensor and it's bang on!
Another thing I noticed was that there was a small amount of oil in the airbox and the throttle bodies seemed quite dirty!
My thoughts are balance and clean the injectors, not sure how to clean the injectors properly, I assume the balancing is done the same way as with carbs with vacuum gauges?
Any ideas?

Yes balancing the throttle bodies can be done with vacuum gauges - the Workshop manual will give you some good info (as well as telling you how to balance for CO ... but few have the equipment to balance for CO). From your comments I reckon balancing the TBs will make a great improvement.

If you are going to clean the injectors, put some stuff in your fuel - but make sure it's the stuff that works such as BG44-K or Archoil AR6400

Oil in the airbox is not unusual - the engine breather vents into the airbox. Particularly when the oil is over-filled, it ends up in the airbox .... just clean it out.

The workshop manual can be downloaded free from Martin Poll's website (go for the OCR version - it's searchable.
http://www.martinpoll.dk/div_april.htm

Thanks, had a read through the manual today but it specifies the use of Aprilia special tools!
So can I not just use vacuum gauges to sync the TBs?
Is there a guide anywhere with information regarding the balance of the TBs using std vacuum gauges?

Or would any one know the procedure?

Many thanks

Yes - just ignore the bit about setting the CO with the special meter - obviously great if you can do this but better to just do the vacuum balance if (like most) you don't have the equipment.

The other thing it might have mentioned is fitting some vacuum take off adapters below the TBs.
Unless you are unlucky enough to have one of a handful of those Falcos first produced, that won't be necessary as most came with TBs with built-in vacuum take offs.

There's a good guide on Ken's site http://home.comcast.net/~sl_mille/synch.html

Yesterday the throttle bodies were sync'd, since it was dry today I took her for a blast and she feels like a different bike, still a tiny bit of hesitation at 2'500 to 3'500 but overall a complete transformation!
I want to get her checked out on the dyno as soon as I'm able to, to set up the C02 levels but I can certainly live with new performance :D

Thanks for your help!