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Discussion Starter · #1 ·
Hi all,

Anyone install the CR carbs with a TPusa/British customs billet intake manifolds? I tried to tonight, but the carb's throttle shaft fouls on the motor mount and doesn't allow you to slide the carbs forward far enough to fit into the intakes. What is the popular fix? I bought everything second hand, so no destructions or support available from a vendor. Also have interference at my pingel fuel tap, but I can elevate the back of the fuel tank a bit to resolve that issue.

I'm not excited about the prospect of refitting the manifold spacers to move the manifolds back enough to engage the carbs...that might work if nothing else does.

BTW, the billet manifolds have a much better port match than the stock setup. The stockers need to be relieved at the bottom 1/2 of the sides and along the entire bottom to blend into the intake port in the head. The castings are also terribly rough...free HP for those with a dremel, some sanding drums, and a couple hours of free time.

Regards,

--Rich
 

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Hi all,

Anyone install the CR carbs with a TPusa/British customs billet intake manifolds? I tried to tonight, but the carb's throttle shaft fouls on the motor mount and doesn't allow you to slide the carbs forward far enough to fit into the intakes. What is the popular fix? I bought everything second hand, so no destructions or support available from a vendor. Also have interference at my pingel fuel tap, but I can elevate the back of the fuel tank a bit to resolve that issue.

I'm not excited about the prospect of refitting the manifold spacers to move the manifolds back enough to engage the carbs...that might work if nothing else does.

BTW, the billet manifolds have a much better port match than the stock setup. The stockers need to be relieved at the bottom 1/2 of the sides and along the entire bottom to blend into the intake port in the head. The castings are also terribly rough...free HP for those with a dremel, some sanding drums, and a couple hours of free time.

Regards,

--Rich
E-Mail me a pic, maybe I have the solution for you.
 

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Sounds like you had something upside down or switched around . I have the B/C version which is identical . When I first installed them I had one of the mounts on the wrong side which obstructed the bracket and throttle . You can't tell until you have everything on . After I realized what I did I swopped them around and it was good to go.

FYI When mounting the 35s teflon tape or silicone ( lightly ) to seal around where the mounts are . Mine have a light leak and I guess it's a common problem . After sealing them it just makes wonders on how the carbs on the motor perform .
 

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FYI When mounting the 35s teflon tape or silicone ( lightly ) to seal around where the mounts are . Mine have a light leak and I guess it's a common problem . After sealing them it just makes wonders on how the carbs on the motor perform .
I wouldn't use teflon (I use red RTV), but if you're going to make sure you use the yellow teflon tape (not white) as the yellow is rated for fuel contact. The white will dissolve when contacted by gasoline.
 

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Discussion Starter · #6 ·
Sounds like you had something upside down or switched around . I have the B/C version which is identical . When I first installed them I had one of the mounts on the wrong side which obstructed the bracket and throttle . You can't tell until you have everything on . After I realized what I did I swopped them around and it was good to go.
I'm having a hard time visualizing what could be amiss...the carbs were a set that came off another bike (i.e. nothing to assemble) and the intakes are the same right to left (I think?)....


E-Mail me a pic, maybe I have the solution for you.
That sounds like a good idea. Actually I'll post a pic once I get home from work...

Thank you both for your thoughts...

And to Sweat, too, for the input on the sealant/teflon tape.

Regards,

--Rich
 

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Discussion Starter · #7 · (Edited)
Okay, here's a few pics of the setup. The throttle shaft fouls on the upper motor mount when held in position...about 3/8" or so shy of being fully bedded into the intake manifolds.

Doesn't appear that flipping the manifolds over will do anything, but dunno...maybe it will change the angle into the head???

Thanks for any help you can provide...

Regards,

--Rich
 

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Just wondering as I am waiting on a BC kit install. Any issues with the Pingel pertcock clearance?

I have the same one as you.
 

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My other question is this; you bought your kit second-hand, (which is something that I would never do with a serious component to the bike)

Are you SURE that you have compatible components to begin with?

AFAIK and AFAI have read, and according to SEAN at BC, their kit is a bolt on component IE; NO ISSUES. You may have cheaped your way into a problem.

Actually look at this;http://www.british-customs.com/triumph-motorcycle-cr-special-racing-carburetor.html

Looks like something ain't right with your manifolds to me.....They look too long...or bassackwards, or something-whatever, they don't look right.
 

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According to BC's site, they have two different options for the intake spigots. They have standard intake spigots and custom intake spigots. Their photos of the carb show either a much longer spigot or the carb boot isn't pushed as far over the spigot compared to the photos you posted, so that could be your problem.

 

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My other question is this; you bought your kit second-hand, (which is something that I would never do with a serious component to the bike)

Are you SURE that you have compatible components to begin with?

AFAIK and AFAI have read, and according to SEAN at BC, their kit is a bolt on component IE; NO ISSUES. You may have cheaped your way into a problem.

Actually look at this;http://www.british-customs.com/triumph-motorcycle-cr-special-racing-carburetor.html

Looks like something ain't right with your manifolds to me.....They look too long...or bassackwards, or something-whatever, they don't look right.
wow, your input was sooooo helpful.
 

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looks to me like you need to fab a motor mount bracket to clear the carbs as in houston08thruxton pic. it allso looks like those carbs in his pic are longer up front.
 

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Discussion Starter · #13 ·
Actually look at this;http://www.british-customs.com/triumph-motorcycle-cr-special-racing-carburetor.html

Looks like something ain't right with your manifolds to me.....They look too long...or bassackwards, or something-whatever, they don't look right.
What I notice is that the motor mount depicted is a huge arch...whereas mine is straight. The spigots on the carbs are longer as well.

As far as buying second hand parts, the carbs came off a Hinkley twin that was crashed/parted...so its a pretty good bet that they'll work just fine.

Regards,

--Rich
 

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If it was me I dont know how much time and money I would put in to those little carbs.I would sell them and buy some real carbs 39s or 42s
 

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I wouldn't use teflon (I use red RTV), but if you're going to make sure you use the yellow teflon tape (not white) as the yellow is rated for fuel contact. The white will dissolve when contacted by gasoline.

Red RTV is not rated for contact with Gasoline either.

I used it (and black) between two parts of an intake manifold and both fell apart in days.

My 39s fit perfectly into the manifold boots. If there is a poor fit with the 42s or CRs my preference would be correcting it with proper carb spigots versus silicone.
 

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they fit even tighter in the 42s there bigger you know. You shouldnt have to use anything if its right.
 

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What I notice is that the motor mount depicted is a huge arch...whereas mine is straight. The spigots on the carbs are longer as well.

As far as buying second hand parts, the carbs came off a Hinkley twin that was crashed/parted...so its a pretty good bet that they'll work just fine.

Regards,

--Rich
You are right. Click the link again and, click on the silver manifolds option, and it shows the straight bracket.

??????
 

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Okay, here's a few pics of the setup. The throttle shaft fouls on the upper motor mount when held in position...about 3/8" or so shy of being fully bedded into the intake manifolds.

Doesn't appear that flipping the manifolds over will do anything, but dunno...maybe it will change the angle into the head???

Thanks for any help you can provide...

Regards,

--Rich

I have never used that engine mount so if its a problem leave it off.
 
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