Triumphrat

NewOldSkool

Ok so either they Jenks carb book was updated, or I just never noticed that the 790cc Bonnies for 2006 have the richest needles. If I am reading it correctly, they are even richer then the Thrux needle. I have not heard of this before, and I have an 06 790 and was planning on going to the Thrux needles. But now not sure... anybody know anything about this?

Page 10 Carburetor Settings—2007

(From left to right)
Stock Bike
****
Free Flow
Air filter
Only
****
Triumph
"Off-Road"
Exhausts
Only
****
"Off road" exhausts &
free flow Airfilter
****
"Open" exhausts &
free flow Air filter
****
Airbox Removed

790cc Bonneville versions (2001 to 2005)
Stock Needle
Main Jet 110 115 120 130 135 140 [145]
Pilot Jet 40 40 40 42 42 42
Shims 0 0 0 1 1 1 to 2
Pilot Screw 2.5 turns 2.75 turns 2.75 turns 2.5. turns 3 turns 3 turns
Needle Code NAGB NAGB NAGB NAGB NAGB NAGB
Air Hole 2.5mm 2.5mm 2.5mm 2.5mm 2.5mm 2.5mm

790cc Bonneville versions 2006 models 06 Stock Needle
Main Jet 110 115 115 120 125 130
Pilot Jet 40 40 40 40 40 40
Shims 0 0 0 1 1 1 to 2
Pilot Screw 2.5 turns 2.5. turns 2.5. turns 2.5. turns 2.5. turns 2.5. turns
Needle Code NFCD NFCD NFCD NFCD NFCD NFCD
Air Hole 2.5mm 2.5mm 2.5mm 2.5mm 2.5mm 2.5mm

790cc Bonneville versions Thruxton Needle
Main Jet 115 120 128 135
Pilot Jet Not Not 40 40 40 40
Shims Advised Advised 1 1 1 1
Pilot Jet 2.75 turns 3 turns 3 turns 3 turns
Needle Code NBTZ NBTZ NBTZ NBTZ
Air Hole 3.0 mm 3.0 mm 3.0 mm 3.0 mm

790cc America & Speedmaster Stock Needle
Main Jet 110 115 120 125 130
Pilot Jet 42 42 42 42 42 No Data
Shims 0 0 0 1 1
Pilot Screw 1.5 turns 1.75 turns 1.75 turns 2.0 turns 2.25 turns
Needle Code NBAD NBAD NBAD NBAD NBAD
Air Hole 2.5 mm 2.5 mm 2.5 mm 2.5 mm 2.5 mm

790cc America & Speedmaster Thruxton or Speedmaster Needle
Main Jet 122 125 130
Pilot Jet Not 40 40 40 No Data
Shims Advised 2 with NBTZ 2 with NBTZ 2 with NBTZ
Pilot Screw 2 turns 2.25 turns 2.5 turns
Needle Code NBTZ or NBZY NBTZ or NBZY NBTZ or NBZY
Air Hole 2.5 mm 2.5 mm 2.5 mm

856cc Bonneville T100 Stock Thruxton Needle
Main Jet 110 110 115 120 128 140
Pilot Jet 40 40 40 40 40 40
Shims 0 1 1 1 1 1
Pilot Screw 2.5 turns 2.75 turns 2.75 turns 2.5. turns 3 turns 3 turns
Needle Code NBZT NBZT NBTZ NBTZ NBTZ NBTZ
Air Hole 2.5 mm 2.5 mm 3.0mm 3.0 mm 3.0 mm 3.0 mm

856cc Speedmaster Stock Speedmaster Needle
Main Jet 120 122 125 128 130
Pilot Jet 40 40 40 40 40 No Data
Shims 0 1 1 2 2
Pilot Screw 1.5 turns 1.5 Turns 1.75 turns 2 turns 2.25 turns
Needle Code NBZY NBZY NBZY NBZY NBZY
Air Hole 2.5 mm (?) 2.5 mm (?) 2.5 mm (?) 2.5 mm (?) 2.5 mm (?)

856cc Thruxton Stock Thruxton Needle
Main Jet 110 112 118 125 130 140
Pilot Jet 40 40 40 40 40 40
Shims 0 1 1 1 1 1
Pilot Screw 2.5 turns 2.5 turns 2.5 turns 2.5 turns 2.5 turns 2.5 turns
Needle Code NBZT NBZT NBTZ NBTZ NBTZ NBTZ
Air Hole 2.5 mm 2.5 mm 3.0 mm 3.0 mm 3.0mm 3.0 mm

PAAS

Yes, the last of the 790cc Bonnies did have a different needle to the previous years, but I don't know how the taper compares to the "Thruxton" needle. The needle type is engraved on the button head of the needle if you want to confirm which needle you have.

__________________
Paul.

Herts. UK
Aubergine & White 05 T100 (865cc) with numerous mods.
(Previously Ducati Monster S4 and several UJMs)

NewOldSkool

Thanks, I either just never noticed this before or this was a recent update. Has any traded out the 06 790 needles for the Thrux needles and seen any improvement. Going by just the jet selection, it looks like it would be better for me to stay with the stock ones. But not sure if the angles are different or not, and that would effect the power range, right? Any suggestions? Thx
Mondo

RedBird

I would suggest a dyno run to see what is going on in the mid-range. My '03 790 is a little rich with the stock '03 needles with no shims. IMHO, the main jets sizes are "relatively" easy to get close by the seat of the pants; however, I am at a loss to try the mid-range by the seat of the pants.

I have averaged 50+ mpg after setting mine up on the dyno (about 18000 miles ago), and I do not ride timidly--I spool her up to 8100 through the first 4 gears about every time out.

__________________
Larry
2003 T-100 (790cc), NARK, NH Togas, 8100 rpm rev limiter, 158 main jets, 42 pilot jets (less than 1 turn out on pilot screws), stock needles--no shims. 13 A/F ratio from 1100 rpm to 4000 rpm; 12 A/F ratio from 4000 rpm to 6000 rpm; 13 A/F from 6000 rpm to 8100 rpm.:D
2007 Tiger 1050--White:D--SW-Motech crashbars, Skidmarx rear hugger/chain guard, Calsci +7 windscreen.

NewOldSkool

Thx, I just got a reply from Peter at Jenks too about the difference in the needles. From what he gathered, it is almost the same as the T100/Thux needles, but with a little extra from mid range performance. So I think I will be keeping the current needles for now. I might pick up a pair of Thrux needles to see if there is any difference after I get the current ones dailed in (was told will be able the same jetting for both).