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Motorcycle Discussions => British Bikes => Topic started by: johnm on February 03, 2016, 07:57:36 PM

Title: Triumph T90 Amal Carb query
Post by: johnm on February 03, 2016, 07:57:36 PM

Hi everyone
I hope someone  can help with a carburettor issue I have on a recently purchased 1963 Triumph T90. It is fitted with a different spec carb to the original 376 monobloc.  It is a 625 concentric, similar to the MK1.5 with the choke lever on top, which I  believe is of Spanish origin fitted to Bultaco etc.
I have no contacts as to who fitted this and why. The issue I have is should I leave well alone and maybe just service it?  Should I replace it with an original?  Is a concentric any better than a monobloc?
 I am not too bothered about originality a so I do not have a problem with leaving it in place. It seems to run OK with this setup, but with not owning a 350 twin before I don't know if it would run better with the original.
Any help would be appreciated, I am scratching my head a bit on this.
Cheers  John

Title: Re: Triumph T90 Amal Carb query
Post by: mark2 on February 03, 2016, 10:04:19 PM

if its running ok why change , ride the bike

Title: Re: Triumph T90 Amal Carb query
Post by: johnm on February 03, 2016, 10:07:52 PM

Hi Mark, Thanks for that, that's the line I was thinking of taking.

Cheers & regards
John

Title: Re: Triumph T90 Amal Carb query
Post by: mark2 on February 04, 2016, 07:08:23 AM

the twin points is the weak link as far as running on the T90 , replace these and they are a useable nice running bike

Title: Re: Triumph T90 Amal Carb query
Post by: Rex on February 04, 2016, 08:33:00 AM

If it was fitted to a 'Taco, it would be a two-stroke carb, and they ain't the same as a carb for a four-stroke. My old Pursang had a Spanish copy carb and it was sh*te to be honest.
Nice bike, the T90, and I'd spring for a new/reconn'ed carb of the correct type if it was mine.

Title: Re: Triumph T90 Amal Carb query
Post by: mark2 on February 04, 2016, 09:11:40 AM

this is true but I don't think it would run very well at all if it was set up for a two stroke so it must be the same type but setup for four stroke , did they fit two of these too the later triumph bonny ? square type plastic top . found it not the plastic top ones , they did four and two stroke versions

Title: Re: Triumph T90 Amal Carb query
Post by: johnm on February 04, 2016, 10:22:42 PM

Thanks for all the replies, it's given me something to think on.  I may strip the carb down and see what jets etc are in there just out of curiosity and maybe give it a service, I have been in touch with Amal and they say it is the same as the 1600/1900 series MK1.5 and they do do a service kit for it. The bike is fitted with electronic ignition so that should help with running.

Cheers
John