Triumphrat

gabriel · 07-10-2008, 01:32 PM

Hi

I have a 1967 Triumph Bonneville T120 (650) and need to order some new Amal Carbs (930s). The company "Old Brits" is asking for the jetting, needle, cut away specs so they can config the carbs correctly to the bike. While I know I'll need to tweek/tune it, I was wondering where I could find the specs for the initial set up? Can't seem to find anywhere. Your help would be greatly appreciated.

Thanks

Gabe

GrandPaulZ · 07-10-2008, 01:46 PM

The later spec T120 in '67, using the first 930 concentrics, used the following:

220 main
928/060/3 slide cutaway
0.106 needle jet
(needle in middle position)
20 pilot jet (eliminated on later models)

jimmy bush · 07-10-2008, 03:03 PM

This is the response I got from mechannica who really seems to know these old bikes. I bought some new 930's for my 68 T-120 and they came in with 200 mains instead of the 220's I was expecting.

01-15-2008 #2 (permalink)
Mecchanica
Senior Member
SuperBike

Join Date: Aug 2006
Location: Honolulu, Hawaii, America\'s Pacific Paradise
Posts: 1,746 Disregard the manual. Amal changed the design of the Concentric in mid 69 and so those figures are not useful.
Depending on your exhaust......
Stock exhausts, I would start with 200 mains and 106 needle jet (with the cross drilling hole) with the 2 identifier groove needle in the middle position. # 3.5 cutaways on the CHROME slides. Chrome slides are the only way to go. If you have open exhausts, go to 220 mains.
What air filter elements are you using? Paper or gauze? That can make a difference, too.
__________________
Triumph old, Triumph new, any Triumph will do.

gabriel · 07-10-2008, 03:16 PM

Thanks. This project is chopped with open exhausts. So it looks like the 220 is the way to go. Thanks for your help.

Gabriel

DAGAD · 07-10-2008, 03:37 PM

If it were mine, I would go for MONOBLOCKS, EVERY TIME. The concentrics are STILL monkey metal. Just my opinion you understand. If you want jettings for monoblock, let me know.
Roy.

GrandPaulZ · 07-10-2008, 04:04 PM

I'm with Dagad, I've got freshly sleeved Monoblocs on my '67.

Just a FEW of the variables in 1967, another one of those "tweener" years when stuff was changing:

Early........................................Late
Aubergine / Gold paint.................Aubergine / White paint
Gray-topped seat.......................All-Black seat
Monobloc carbs..........................Mark I Concentric carbs
Internal fork damper body............Fork shuttle valve damping

As I am funny that way, I mixed and matched to my preference when I refurbished my '67 - all "early" condition items listed above except the paint job. I just like the White better than Gold on the top coat, although the whole thing was properly laid on a base of Gold metalflake per Don (Triumph man) Hutchinson. I also have a late '69 spec bolt-on grab bar that came with the bike but is totally incorrect for '67. So shoot me.