CORRECT CARBURETTOR STUDS

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Rob Harknett
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Re: CORRECT CARBURETTOR STUDS

Post by Rob Harknett »

correct parts as per parts list is Manifold stud 011634 1 11/16" x 1/4" 26 & 20 tpi. Carb stud 1 1/32" x 5/16" 26 & 22 TPI. 26 tpi are the ends that takes the nuts. If different your bike has probably been modified. Why do you feel your bike needs to run cooler? If it is running hot, I would think the problem more like incorrect carb settings or you are running it retarded.
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sunnybob
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Re: CORRECT CARBURETTOR STUDS

Post by sunnybob »

Rob Harknett wrote:correct parts as per parts list is Manifold stud 011634 1 11/16" x 1/4" 26 & 20 tpi. Carb stud 1 1/32" x 5/16" 26 & 22 TPI. 26 tpi are the ends that takes the nuts. If different your bike has probably been modified. Why do you feel your bike needs to run cooler? If it is running hot, I would think the problem more like incorrect carb settings or you are running it retarded.
Rob, I have made a mistake. I ordered long manifold studs from the club but now I realize they are manifold to head studs. I need carb to manifold studs. I have original one, they are 1 1/32" x 5/16" 26 & 22 TPI. 26 tpi are the ends that takes the nuts. To fit a spacer I need them longer.

I live in Milano, Italy. Weather is usually warmer than England (yesterday we had 37° celsius). I mostly drive in traffic and my problem is the heat of the carb after stopping. It causes gas control locking until it get cooler again.

Do you know where to buy some longer carb to manifold studs, please?
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Rob Harknett
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Re: CORRECT CARBURETTOR STUDS

Post by Rob Harknett »

sunnybob wrote:
Rob Harknett wrote:correct parts as per parts list is Manifold stud 011634 1 11/16" x 1/4" 26 & 20 tpi. Carb stud 1 1/32" x 5/16" 26 & 22 TPI. 26 tpi are the ends that takes the nuts. If different your bike has probably been modified. Why do you feel your bike needs to run cooler? If it is running hot, I would think the problem more like incorrect carb settings or you are running it retarded.
Rob, I have made a mistake. I ordered long manifold studs from the club but now I realize they are manifold to head studs. I need carb to manifold studs. I have original one, they are 1 1/32" x 5/16" 26 & 22 TPI. 26 tpi are the ends that takes the nuts. To fit a spacer I need them longer.

I live in Milano, Italy. Weather is usually warmer than England (yesterday we had 37° celsius). I mostly drive in traffic and my problem is the heat of the carb after stopping. It causes gas control locking until it get cooler again.

Do you know where to buy some longer carb to manifold studs, please?
I did wonder if there was some miss understanding about the 2 studs, which is why I gave pt. no. name of part and sizes for both studs.
There is a long stud pt. no. 011628 used on twins that goes in the crank case 5/16" ( 22tpi end ) then holds on cylinder and head ( 26tpi end ) It is 5 7/16" long. This would give material to make two studs, but you will need to make new 26 tpi thread on one half and new 22 tpi thread on the other half.
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Re: CORRECT CARBURETTOR STUDS

Post by leswaller »

Roberto, yes PO means previous owner (or owners)
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ajscomboman
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Re: CORRECT CARBURETTOR STUDS

Post by ajscomboman »

Err, Guys forgive me if I'm wrong but I thought that by giving the correct part number the first place to look to buy would have been the parts service. Only got 96 of them in stock!
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Rob Harknett
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Re: CORRECT CARBURETTOR STUDS

Post by Rob Harknett »

There's been some misunderstanding Rob. I believe Roberto did get parts from the club. Due to the miss understanding between manifold to head, and carb to manifold studs, got the wrong parts. However since then Roberto has wanted longer carb to manifold studs, so he can fit a carb spacer. To help cure a hot running problem in Milano. That is why I suggested he got the 5/16" twin stud that goes in the crank case to hold the barrel and head. It has correct threads each end. This stud will provide material to make 2 longer carb studs, leaving a 26 tpi to be made on one 22 tpi the other. Ending up with 2 longer than standard carbs studs, correct dia and threads each end.
I do believe club spares have the twin stud in stock.
I think I have summed the progression of the topic up correct.
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ajscomboman
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Re: CORRECT CARBURETTOR STUDS

Post by ajscomboman »

Rob a Model 20 with the correct studs will accommodate a standard insulator for a twin without the need for longer studs (got them on all my twins). Anything thicker than the standard insulator will not allow the carb to be removed easily without resorting to bolts like the pre 56 and 60's onwards models. I was aware he ordered the wrong studs from the club so why then ask where to buy from once I'd given the correct number, surely a return to the parts service with the correct number would have been the first logical action.
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Rob Harknett
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Re: CORRECT CARBURETTOR STUDS

Post by Rob Harknett »

ajscomboman wrote:Rob a Model 20 with the correct studs will accommodate a standard insulator for a twin without the need for longer studs (got them on all my twins). Anything thicker than the standard insulator will not allow the carb to be removed easily without resorting to bolts like the pre 56 and 60's onwards models. I was aware he ordered the wrong studs from the club so why then ask where to buy from once I'd given the correct number, surely a return to the parts service with the correct number would have been the first logical action.
Understood Rob. That does give Roberto all the info he needs to easily fit a spacer. Hopefully Roberto will understand and do has you suggest above.
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sunnybob
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Re: CORRECT CARBURETTOR STUDS

Post by sunnybob »

Rob did a perfect summary :beer:

I bought the spacer because seems the best way to go cooler. I didn't know about any insulator and if I put this word in amoc search I had no response and I 'm not able to see it in the carb section of the shop. I would appreciate its part number with the part number of longer carb to manifold studs, if they exist. Sure it is my fault, but in my opinion the online shop could be more accurate!

I found a 3mm insulator on a famous Royal Enfield shop, probably I can manage to make it fit my studs but for sure there are not 3mm to waste actually. Anyway I found some other solutions. I found and bought from a British bikes parts store here in Italy two 5/16 tpi 22 bolts that can fit if I split the spacer. Otherwise there are some longer 5/16 tpi 22 Triumph head bolts that could fit it but they have not them in stock (part number 680035). There is lots of space in the back of the carb as I do not have the air filter, so there is not problem to use longer 5/16 bolts with the standard spacer.

Thank you, I really appreciate your help.
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ajscomboman
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Re: CORRECT CARBURETTOR STUDS

Post by ajscomboman »

Bolts will be fine although a bit more fiddly to refit the carb as opposed to when studs are fitted. The later 60's twins had to revert back to using bolt as the new type manifold didn't allow the use of studs due to a lack of clearance when trying to fit and remove the carb for servicing. Looks as though you've cracked the problem though. :beer:
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