Working on a Triumph Other Motorcycle Manufacturers Discuss Working on a Triumph in the Motorcycles forums; Anyone know if there is a kit available to run a 2 into 1 intake manifold on a 1971 T120 Bonneville without changing cylinder heads?...

[aceharleywrench]

Anyone know if there is a kit available to run a 2 into 1 intake manifold on a 1971 T120 Bonneville without changing cylinder heads?

[evoKENevo]

Hi,Ace
I highly doubt that a manifold like what you're asking about ever existed. Because unlike the single carb heads (TR-6) that have their intake ports coming in directly from the rear (with a Y type manifold) the dual carb heads (T-120) have their ports coming inward on an angle from either side...which would reguire a manifold like that to make a virtual U turn.

But,here's a link and phone # to the people who should be able to answer your question for sure...and be able to get you one IF one exists


British Only Motorcycles & Parts Inc. Triumph, BSA and Norton Motorcycle Spares

1-800-278-6659

BTW..why would you want to do that anyhow ??

[Wrightturn]

Hey Ace,

I agree with Ken. I have never seen one. If any place on the planet has one it will be MAP. Try www.mapcycle.com they are in St Pete Fla at (727) 381 1151. I know they have one to convert a Norton to single carb. With an electronic ignition and a single Mik it was a different bike.

If they can`t help you are looking for a T6 head. Try Georgia Cycle. Couple years back I had a bunch of them. Need any Amal stuff ????

[aceharleywrench]

Thanks for the quick replies,guys.I didn't think that anything was available because of the splayed mounts,but figured I'd give it a shot.Customer wants to run a single carb but I doubt he's gonna want to spring for a new head.

[evoKENevo]

Hey,Ace
You're more than welcome...and if your friend does decide to spring for another head..just keep in mind that some of the earlier model Triumph heads do not have a center head bolt or hole (between cylinders) like his '71 does...and, of course, he'll want one that does.

[aceharleywrench]

Already shell-shocked him with head replacement talk (who would've figured?) I guess we'll go with twin Mikunis.I figure 30 or 32mm should be about right,any feedback?

[evoKENevo]

Ace
It's been so long since I've played with Triumphs, I can't even recall what size carbs the Amals were...and that's all I used on them,prefering reworked mono-blocs over the concentrics. Maybe Wright can help you more with that Meanwhile,have you guys made any performance mods to the bike,that might help to know about ??

For whatever it's worth...on my last one,I remember going with 11:1 pistons,,Q cams and R tappets (all factory TT parts) with a single mono-bloc on a TR-6 head...and was out-running mostly-stock Honda 750 fours,waaaaay back then...before Mikunis had "caught-on" around here.

[aceharleywrench]

It's been quite a while since my last Trumpet,I remember ordering so much stuff from British Cycle Supply in Nova Scotia that even now,20 odd years later,I still remember the VIN (TR6RPC02960) even though I haven't seen the bike in decades.Funny how some things stick with you.

[Buzz Kanter]

For Triumph motorcycles and other cool British bikes check out "]Jockey Journal - very cool site.

[aceharleywrench]

Wow,deja vu all over again,I could have sworn I posted a reply to this thread last night (along with several others) that seems to have disappeared along with my newly acquired "senior member" status. Long story short,the customer came by with a box of parts he got with the bike & there were a pair of 32mm Mikunis in amidst all the junk. I am in the process of resurrecting said Mikunis from the old gas graveyard and am hopeful I can get this thing done and gone before too long.Thanks for the input,I have more posts to redo.Later.....