[Tastee Twirl]

Hello all just pick up 1968 t100r . But it has t100c motor is this a comon switch . Runs well enough tach not work and speedo not evan a cable on it . But been riding it Not like it fast so .
Last ?? Should i be run a lead subistute thanks for any replies

 

[pookybear]

Hello all just pick up 1968 t100r . But it has t100c motor is this a comon switch . Runs well enough tach not work and speedo not evan a cable on it . But been riding it Not like it fast so .
Last ?? Should i be run a lead subistute thanks for any replies

Welcome to the forum Tastee Twirl. Someone with some
knowledge with the 100s hopefully will chime in for your
answers. But wow, quite a few sentence fragments, where
you a rebel in school as well? Take that one as a light joke.
You will be able to catch me on spelling later.

Pookybear

 

[jimballard]

Welcome Tastee,

Good thing you aren't near me........ice cream is one of my basic food groups, right along with fast, frozen, pre-prepared and take-out! Now to get serious, if it's a T100C engine, it didn't come with a tach drive set-up on the engine. That's not to say that a previous owner didn't transfer the unit to it when the swap was done. Check on the engine case roughly in front of where the vin # is stamped and see if there's just a bolt in it or a cylindrical piece with a cable (or at least threads on the top to accept one). The tach drives off the exhaust camshaft so this should give you an idea where to look. It should be almost straight back from the upper engine mount bolt on the frame bracket.

A bit long-winded, I know, but I hope it helps you: Jim

 

[Woody1911a1]

to add to what jim said . the prev owner who did the engine switch might have just screwed the tach drive in not knowing that the t100c didn't have a drive thimble on the ex cam to drive it .

also yes you do need a speedo cable for it to work

the instrument drives are prone to failure as are the instruments themselves . you need to do some diagnostics to find out where the faults are .

oh and Welcome

cheers , Woody

 

[Tastee Twirl]

Thanks for info I will check it out when i get home tonight . So even with cable in the tach it not going to work cause their no drive thimble . Is this somthing that can be added or not .

So is this an ok bike or an iffy type of thing I traded a van worth 1k for it. Sorry for my bad gramer in first post . I'm also trying to get some pic so you all can check out my mug shot and scooter .

THANKS AGAIN
TASTEE

 

[t100rc]

Triumph 500s are fine bikes ... I have one which I ride ... a lot ... and I love it!

The speedo cable is an easy enough fix, provided the speedo drive is still good ... often, the cable is removed for a reason, though. In the worst case scenario, you'll need to pull the rear wheel to replace the drive box. However, that doesn't mean the speedo is gonna work. Those magnetic Smith's gauges have a pretty short life span. Rebuilt units are available and there are people who rebuild them ... there are also cheap knock-offs available (I see them on ebay all the time) that I've heard work just fine if you don't care about originality.

If you remove your tach drive and shine a light in there, you should be able to determine if your cam has the drive slot or not. The slot is a separate piece that you can add. If it does have the slot, reinstall the tach drive and tuen the motor ... if the output of the drive unit does not spin, you may have the incorrect tach drive ... the 650 and the 500 drives look almost identical, but the 650 one is a little longer and the drive gear won't reach the camshaft. It is also likely that the gauge itself is broken ... as I said ... they wear out.

Welcome aboard ...

 

[GrandPaulZ]

If the twirly bit (drive thimble) isn't there, you have to split the cases to install it.

 

[Tastee Twirl]

A pic

Hey thanks for all info as to anyone on lead in gas ?

 

[t100rc]

Most seem to just run pump gas and adjust timing accordingly. Triumph engines can take it ... I do mix my fuel to be higher octane and leaded using Octane Supreme which is tetra ethyl lead ... not a substitute.

 

[thekeyman]

l too have a T100 and they are handy little bike. The single carb versions are best as they are easy to work on and keep in tune. As said before the speedo should be fixed but you can live without the tacho, l don't think l have looked at it while riding in years!. lf you are going to have to split the cases to fix it, forget it. Tell everyone it works and drive away before they find out your'e lying!!. They can keep up with traffic in town but not out on the highways , 70 mph is tops for any distance but will go all day at 65 and with little vibes too, a German pal borrowed it to go to the Isle of Mann and was impressed, not bad as hes a BMW rider. Run it on super unleaded with an occasional spoonful of additive if you are worried about the valves but mine has been without lead for fifteen years.

 

[jimballard]

By the way, I do believe that the threads used to hold the tach drive housing into the case are LEFT HANDED ones. Check to be sure.

No need to add to the problems: Jim

 

[Tastee Twirl]

Thanks again . I was also looking for repair and parts books any good ideas ? aAso got some oil coming from head took a quick pic thinking a head gausket maybe ? Also the cable in pic is where tach cabel is in .

 

[t100rc]

Left-handed threads for the tach drive started in '69.

 

[Jon Hardcastle]

Thanks again . I was also looking for repair and parts books any good ideas ? aAso got some oil coming from head took a quick pic thinking a head gausket maybe ? Also the cable in pic is where tach cabel is in .

A T100R was my first bike, even with my Scrambler and Tiger I still miss her. Of the vintage twins, the 500's were the smoothest IMHO. As for the gaskets, I would replace them with some new ones from here. http://www.britgaskets.ca/trigaskets.html

As for Unleaded gas, I never had an issue with it. Enjoy, you have a lovely bike there. Don't ever sell it!

 

[pookybear]

Thanks again . I was also looking for repair and parts books any good ideas ? aAso got some oil coming from head took a quick pic thinking a head gausket maybe ? Also the cable in pic is where tach cabel is in .

Oh boy, Tastee Twirl,

Always fun starting out on a new and different project. No oil
will naturally come from a head gasket. So maybe look a little
higher up at the rocker boxes, the gaskets at the base and there
is an o-ring at the end of the shaft that like to leak. Also there
will be two tubes from the head to the base of the cylinder barrels.
One in front and one in the back, these are for the push rods.
The seals at the top and bottom of these tubes are known for
leaking a little as well.

And yes the cable in the picture at the front of the engine is
for the tachometer, the small part going into the cast is the
right angle drive for the tachometer.

Pookybear