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I’m trying to recreate the bike I had in my youth. It was basically a late 50s/60s Tiger100 (or a 5TA franked up with t100 internals). I know it had 17 wheels. The question I have is this.

If I was to buy a later Tiger100 eg 1970 with 18R and 19 F wheels, can I simply swap the wheels out for 17s? Or did the later bikes have different frames/forks/shocks?

(Btw I am not looking to build this from already butchered bikes not bust up a pristine model).
 

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Hi,

Firstly, welcome to the Forum. :)

If I was to buy a later Tiger100 eg 1970 with 18R and 19 F wheels, can I simply swap the wheels out for 17s?
Ye-ea-ah ... but decent 17" tyres haven't been available for decades ... Fwiw, back in the 1980's, a girlfiend who suffered from Duck's Disease (bum too close to the ground - her joke) had a C-range bitsa ('66 engine in '60 cycle parts) and even then we used 18" wheels for decent tyres.

Also, before '71, it was only US-market T100 versions that had 19" front with a 4.00x18 rear tyre; 'UK & General Export' versions had 3.25x18 front and 3.50x18 rear. Those exact sizes are available in Dunlop K82 (or you can go 3.00 front and 3.25 rear) or you can use 90/90x18 front and 100/90x18 rear from several tyre makers.

did the later bikes have different frames/forks/shocks?
The big C-range cycle parts changes came between '66 and '67. '67-on got a completely new frame, that was deliberately designed to use as many 650 parts as possible - the whole front end, oil tanks, sidepanels, battery carriers, seats, rear mudguards, blah. '71-on, when the 650's went OIF, the T150 remained 'dry frame' with the T100 so there are still common parts. (y)

Pre-'67 did have quite a lot of parts in common with the 650's, but not things like steering bearings and fork yokes, and the different pre-'67 frames and fuel tanks are a 'mare.

Hth.

Regards,
 

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Hi,

Firstly, welcome to the Forum. :)


Ye-ea-ah ... but decent 17" tyres haven't been available for decades ... Fwiw, back in the 1980's, a girlfiend who suffered from Duck's Disease (bum too close to the ground - her joke) had a C-range bitsa ('66 engine in '60 cycle parts) and even then we used 18" wheels for decent tyres.

Also, before '71, it was only US-market T100 versions that had 19" front with a 4.00x18 rear tyre; 'UK & General Export' versions had 3.25x18 front and 3.50x18 rear. Those exact sizes are available in Dunlop K82 (or you can go 3.00 front and 3.25 rear) or you can use 90/90x18 front and 100/90x18 rear from several tyre makers.


The big C-range cycle parts changes came between '66 and '67. '67-on got a completely new frame, that was deliberately designed to use as many 650 parts as possible - the whole front end, oil tanks, sidepanels, battery carriers, seats, rear mudguards, blah. '71-on, when the 650's went OIF, the T150 remained 'dry frame' with the T100 so there are still common parts. (y)

Pre-'67 did have quite a lot of parts in common with the 650's, but not things like steering bearings and fork yokes, and the different pre-'67 frames and fuel tanks are a 'mare.

Hth.

Regards,
Stuart - many thanks - it is a big help and confirms my suspicions that something happened mid 60s. As I said I am trying to recreate an early 60s “C-range bitsa”I had. Because of that I want to try to stick with the 17s.

The one I had was particularly quick (compared to all the other 5TAs around). The received wisdom at the time (late 70s) was that it had a close ratio box (but coulda been just gearbox sprocket or engine sprocket size - any thoughts?).
It may also have had non-standard 5TA cams - maybe from T100??any thoughts in that?
It also had a single mikuni (it idled!) twin points rather than distributor and high compression pistons too.

As an aside, and in the unlikely chance you may know him, it was put together by a guy called Dave Adlesberg (he might even be on the forum somewhere).
Id be interested to know your thoughts on where best to start if you were looking build something like this.
 

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There is a recent book on the c series. I have it but haven't had more than a scan of it
 

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There is a recent book on the c series. I have it but haven't had more than a scan of it
Thanks Dave M - i see a copy of it in my future
 

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Hi,

trying to recreate an early 60s “C-range bitsa”I had.
(late 70s)
Mmmm ... bear in mind that's getting on for half-a-century ago :eek: and the 'old Triumph' landscape has changed beyond recognition in that time. Then C-range parts were abundant and cheap - Mate O'Mine put together the basics of my T100 in the mid-1980's and pretty-much all bar the crankcases was NOS. Now, people have been interested in C-range bikes for a good decade - 650's have been ridiculously-expensive for longer so putative twin owners turned to the C-range, particularly the 500's; more recently, ageing 650 owners have turned to 'em for being smaller, lighter and easier to kick over.

At the same time, "standard" has become far more desirable than bitsa - my T100 is a bitsa now but I specifically acquired many of the missing standard parts twenty-odd years ago (I hope they're still in the plastic crate in storage ...).

Hard to say which'll be the best route to recreating your dream. From parts is probably unwise - twenty years ago, Yeomans and a couple of others were still breaking old Britbikes; unless they're still doing it, individual bits on autojumble stalls are probably individual bits 'cos they're really scrap - purchased and then hawked around because the purchaser looked closer and realised they were scrap. :rolleyes:

Britbikes intended for restoration do still return from the US but you'd be wise to acquaint yourself with the hoops for getting an age-related reg. - ime, you do not want to build your bitsa and it be awarded a Q plate just because you jumped through the hoops in the wrong order ...

If you do consider something "intended for restoration", be realistic about the cost and availability of missing parts - while a better '69-on engine will fit in a pre-'67 frame, '69-on oil tank and/or sidepanel (say) won't fit on the same frame without making something non-standard (if you do, try not to make mods. that are only reversible with great expense).

Also find out the modern cost of things like the 17" wheels - as I posted earlier, you'll almost certainly have to have hubs with larger rims relaced.

And be realistic about brakes. In the 1970's, disc-braked cars were a rarity; today, (virtually?) nothing doesn't have dinner-plate-size discs and multi-pot calipers on every wheel. Unless you're going to potter about only in the Scottish or Welsh highlands, ime a SLS front brake is likely to freak you if you haven't used one since the heyday of your “C-range bitsa”. :whistle:

The one I had was particularly quick (compared to all the other 5TAs around).
Which 'fraid isn't saying a lot today, a Chinese twist-'n'-go will give it a run for your money ...

Many C-range 500's were fitted with an 18-tooth gearbox final-drive sprocket, but it can make 'em feel 'busy' at speed. For what I want out of my T100, it's got 19-tooth gearbox and 46-tooth rear wheel; I wouldn't mind trying a 43-tooth rear but I have to find a QD drum ...

It may also have had non-standard 5TA cams - maybe from T100?
T100 had higher compression and different cams from the 5TA.

Hth.

Regards,
 
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