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Discussion Starter · #1 ·
i am doing the bigbore for my 500 and i am wondering if i order oversize valve or standard from kibblewhite 7mm conversion. also do i need bigger carb jets etc..


thanks in advance.
 

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Hi Heavyd. What do you mean, 'big bore kit' I am not familiar with a kit for the unit 500, can you enlighten me please? Regarding valves, I don't think you can get much bigger in the head? Regarding jetting the carbs, YES you will have to alter your current settings. It might require going up a size on the carb body (926 - 928).
Roy.
 

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Hi Heavyd. What do you mean, 'big bore kit' I am not familiar with a kit for the unit 500, can you enlighten me please? Regarding valves, I don't think you can get much bigger in the head? Regarding jetting the carbs, YES you will have to alter your current settings. It might require going up a size on the carb body (926 - 928).
Roy.
I believe JRC has a 530 kit.

Personally I think a big bore kit on a 500 is a little pointless, but to each his own I guess.
 

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I doubt the extra 6% capacity will be noticeable. In any case the t100's are 'Big Bore' 350's :) Now the jump from 350 to 500 ( about 40% ) is noticeable :)

Incidentally, I notice that the part numbers for 350 conrods are different from the 500's. I can only assume they use a different size wrist pin, as I know the big end journals are the same.... what gives.
 

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A 60 thou re-bore would give you 10cc more but you would never notice it. Therefore I doubt if you would notice 30cc. However you would notice a properly gas flowed head, especially if you had new valves, seats, springs etc. Hotter cams are also an option. Try Kent Daytonas www.kentdaytonas.co.uk for all things relating to 350 and 500cc Triumphs.
 
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Discussion Starter · #6 ·
im going for the sludge trap

thats what started this mess in my basement. this bike has had some owners before and i imagine the sludge trap is gunked up. i own a machine shop as well so the rebore is no biggy. new valves and springs are definently in the plan i will get my local britbike guy to do that part. what do you mean by hotter cams? ill check out kent daytonas.

thanks guys
 

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A 60 thou re-bore would give you 10cc more but you would never notice it. Therefore I doubt if you would notice 30cc. However you would notice a properly gas flowed head, especially if you had new valves, seats, springs etc. Hotter cams are also an option. Try Kent Daytonas www.kentdaytonas.co.uk for all things relating to 350 and 500cc Triumphs.
Even making sure the joins between carb manifolds and head are properly blended can make a real difference... I was right about HeavyD wanting to spend money. I think that big bore kit involves using 650 pistons and a prayer to the cylinder gods that they wont leave you with bored through walls. I have emailed kent daytonas twice with request for information/price. and had no response whatsover.. are they still trading ??
 

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the 530 big-bore kits come with barrels . many of the dealers sell them . rabers say theirs are JRC . i really haven't looked into them just seen them advertised .

i'm not sure what it entails but i can't see getting 40cc's more with just piston diameter w/o machining out the cases . maybe they can . i've heard from reliable sources that you can use std 650 pistons for .080 rebores w/o problems .

cheers , woody
 
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Discussion Starter · #9 ·
the kit comes with

barrel, pistons, rings etc.. my original barrel is rusted and dinged up pretty bad so when i saw the kit i figured adding that and some new lightwieght valves could give me a bit better performance and looks. this is my first project bike my house smells of oil and gasoline, i am kepping every part labeled in my old fishing tackle boxes and spend almost all my spare time working on this bike my wife(newely married) is constantly trying to pull me out of there, its fantastic.

thanks for the advice i certainly will need some more as it continues.
 

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Hey Heavyd. The novelty of wrenching the bike will wear off after 30 years and then the newly married wife will not be new any more. Spend some quality time with her, the bike will wait and then you will both enjoy it later in the year. Just my thoughts?
By the way, did I say that my old workshop is now her new kitchen!!!!!!!
Roy.
 
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