General Which carb?

[timgarman]

Hi Folks
Hoping for some advice on which carbie to go for. My 500's a 1966 500-F.

I've had the engine re-bored out to 600. Mine has the original Weber carb, but I've read a lot about the famed Dell'Orto FZD. Well I tracked one down in Italy but I'm quoted 700 euros. Possibly out of my price range.

I have purchased the Dell'Orto FRG 28/30 which was way cheaper, but I'm told this is not a Carb you can tune?

There is also the possibility of the Dell'Orto FZD 24/30 which is more than the FRG but half the price of the FZD 28/32.

Any advice or comments on any of these carbs?

 

[Toshi 975]

Are you thinking of other engine mods as in camshaft, cylinder head and exhaust ?
The inlet port on the 500 head is 26mms diameter as opposed to 30mms on the 652ccs head so a modest upgrade could be to open up the inlet to 30mms and fit a 126 carb and spacer.
Another carb you did not mention is the twin choke Weber 30DIC. Another rare carb but I did manage to do a trade and get one from a guy in New Zealand

 

[the hobbler]

Morning Tim;
Another carb that can be used is the Weber 30DGS--this was the carb used on the Panda 30. This was an 'Italy only' version of the original Panda and used a version of the old 652cc 126 engine (but running in the opposite direction, sadly). I have 1 available, complete with the original Panda 30 manifold, which is surplus to requirements. This is a better carb than the DIC, (its initials give it its rude nick-name) and being that it came off a Panda, would be jetted pretty well OK. It can be run with its original manifold, although it will sit at a slight angle, but a correct, upright manifold is fairly easily available. The Dellorto 30/24 FZD can be used--it looks pretty well identical to the 32/28 and uses the same manifold but I don't know how well it is jetted.
I am seriously looking in to fitting a HS2 SU carb (1 1/4 choke, same as the 32/28 and uses the Dellorto inlet manifold), but I haven't worked out the correct needle yet--so that is still in the future.
Let us know which way you go, let me know (directly) if my carb is of use to you.

 

[timgarman]

Are you thinking of other engine mods as in camshaft, cylinder head and exhaust ?
The inlet port on the 500 head is 26mms diameter as opposed to 30mms on the 652ccs head so a modest upgrade could be to open up the inlet to 30mms and fit a 126 carb and spacer.
Another carb you did not mention is the twin choke Weber 30DIC. Another rare carb but I did manage to do a trade and get one from a guy in New Zealand

Hi Toshi.
I have a sports exhaust waiting to fit. Other than the 600 re-bore and the carb, that was all I had in mind.

 

[timgarman]

Morning Tim;
Another carb that can be used is the Weber 30DGS--this was the carb used on the Panda 30. This was an 'Italy only' version of the original Panda and used a version of the old 652cc 126 engine (but running in the opposite direction, sadly). I have 1 available, complete with the original Panda 30 manifold, which is surplus to requirements. This is a better carb than the DIC, (its initials give it its rude nick-name) and being that it came off a Panda, would be jetted pretty well OK. It can be run with its original manifold, although it will sit at a slight angle, but a correct, upright manifold is fairly easily available. The Dellorto 30/24 FZD can be used--it looks pretty well identical to the 32/28 and uses the same manifold but I don't know how well it is jetted.
I am seriously looking in to fitting a HS2 SU carb (1 1/4 choke, same as the 32/28 and uses the Dellorto inlet manifold), but I haven't worked out the correct needle yet--so that is still in the future.
Let us know which way you go, let me know (directly) if my carb is of use to you.

Hi Hobbler
Thanks for the tips. Will do some more investigating. Panelbeating is taking an age, so there's no hurry. Will say no to your 30DGS, but thanks for offer!

 

[Toshi 975]

I asked about other mods as in my experience getting a bit more from the two cylinder engine without going crazy about speed at the expense of reliability is a bit of a quadratic equation hence the four aspects I mentioned. Bearing in mind that the design for this great little engine would have been on the drawing board about 60 years ago in the days when side valve engines were still quite common there is scope for improvement without throwing the Bambina out with the bath water. I took a cylinder head to a guy that specialised in racing old motorcycles and his verdict was that the head had loads of scope for improvement. So ended up with porting , larger inlet valves , etc. and running with a late 126 camshaft , 28IMB carb and a modest sport exhaust I had a 499ccs engine that would rev to over 6,500 rpm and go up hills a little better

 

[timgarman]

I asked about other mods as in my experience getting a bit more from the two cylinder engine without going crazy about speed at the expense of reliability is a bit of a quadratic equation hence the four aspects I mentioned. Bearing in mind that the design for this great little engine would have been on the drawing board about 60 years ago in the days when side valve engines were still quite common there is scope for improvement without throwing the Bambina out with the bath water. I took a cylinder head to a guy that specialised in racing old motorcycles and his verdict was that the head had loads of scope for improvement. So ended up with porting , larger inlet valves , etc. and running with a late 126 camshaft , 28IMB carb and a modest sport exhaust I had a 499ccs engine that would rev to over 6,500 rpm and go up hills a little better

Sounds awesome. I've got a lot to learn on the mechanical side. Touching base with guys at the Forum is invaluable.
Thanks.

 

[Toshi 975]

Well if you take another trip back to Horopito there were two 850 Sport Coupes out back with complete engines so you could pick up a Weber 30DIC on your doorstep. For some reason these carbs seem to get bad press but I have run one on an 850 Sport and an 850T van with a sport engine and they worked well. Yet to get to trying one on the 500 or 126 but I have seen quite a few with them fitted.

 

[timgarman]

Hi Toshi. An inspired comment. I was already looking at my diary, seeing when I could give myself a day off to take a drive there. Just an hour away. I've already had a quarter light and a few other bits n pieces off 500's there.

 

[the hobbler]

Evening Tim;
Look on google---'Webber 30DIC twin choke carb--club 126'--has quite a lot of info/comments regarding 30DIC vis-a-vie 30DGS--might be of interest/help/hindrance to you.
Just to throw a complete 'curved ball' into the game--Proietti in London are now marketing a 'large bore carb' a 29IMB--£145---bolts straight on to the standard carb mount--might be all that you need.

 

[timgarman]

Evening Tim;
Look on google---'Webber 30DIC twin choke carb--club 126'--has quite a lot of info/comments regarding 30DIC vis-a-vie 30DGS--might be of interest/help/hindrance to you.
Just to throw a complete 'curved ball' into the game--Proietti in London are now marketing a 'large bore carb' a 29IMB--£145---bolts straight on to the standard carb mount--might be all that you need.

Thanks again Hobbler. Now I'm spoilt for choice. I'm going to check Horropito Motors on Thursday, just incase there's hidden treasure there. What I'm gleaning from the comments are that the 30DGS or DIC (or the FZD 32/28 or 30/24) or the late-comer 29IMB are all better options than the original Weber 26IMB or the FRG 28 that I have?

 

[the hobbler]

Evening Tim;
Decisions, decisions--tough old life innit?---the beauty of the 29IMB is that it is basically an opened up '28', so fits straight on with no mods--linkage, inlet tube, filter--they all just fit straight on. I am led to believe that parts for the FRG are very difficult to obtain outside of Italy.

 

[timgarman]

Hi Hobbler.
Speaking of being spoilt for choice, and not really knowing what I'm looking for, I've just found a Dellorto FZD 32/26 near me, that should cost me around $250 NZD or around £125. Would that work?

 

[the hobbler]

Morning Tim;
At that sort of price--go for it. This version is listed on e-bay (in Italy) for the fiat 500/126. As far as I can see, the inlet manifold (and go for the best you can afford) is the same for all the FZDs. you jammy b----r!

 

[timgarman]

Hi Folks. Thought I'd post pictures of what I found. FZD 32.26 at Horropito Motors in NZ. Cost me $250, around £125.

I know there are some parts missing, which I need to source. If anyone can tell me what they think might not be here, that would be helpful.

 

[Bambino]

Tim,

Congratulations on your purchase. I've attached a few photos of a complete, functional FZD as well as the schematic diagram. Hope they help.

If you want more detailed shots, please let me know.

Some parts are available at http://www.dellorto.co.uk/merchandise/products.asp?CategoryID=1&PartsectionID=80

The 24.30, 26.32 and 28.32 will all work with the 500 engines.

Chris

 

[timgarman]

Thanks Chris. I'd already found the schematic parts diagram. But that confirms I'm on the right track – just as valuable.
The pictures will be very helpful.
I've been advised to rebuild with the original Webber and get it running, then put the FZD in.

 

[Bambino]

I've been advised to rebuild with the original Webber and get it running, then put the FZD in.

Sensible

Chris

 

[timgarman]

One more question regarding carbs. The FZD seems to need some kind of adaptor to link it to the manifold that sits on top of the heat shield. (Hobbler - you mentioned buying the best one I can afford). I assume this is a manifold that links the bolt shafts from the engine to the holes on the FZD, they don't line up without it.
Are there options, where do they come from and what sort of money?

 

[Bambino]

The manifolds are available and cheap(ish).

Found these photos of an FZD mounted on a 500 engine and the manifold. Mine looks the same.

The manifold bolts directly to the intake port on the head and the carby attaches to the other end with a gasket between.

Is this what you meant?

If you mean the throttle linkage, then that is easy as well and is seen in the photo.

Chris