Featured T120v On The Lift

I like a new project



I've rebuilt the 1972 T120V engine with 750 Barrels and a Tiger's head.
Nice 2inch stainless zorsts that should keep the mobile phone users from stepping into the road.
New built wheels with Italian 3 inch rear rim and 2.5 inch front.
Gonna try for a Trackmaster tank on this one.

 

@Iron: All the best for this project. It looks great.

 

Looking good so far mate

 

@Iron Same here mate. Good luck as if you need it. I have seen some of your rebuilds.

 

Thanks Gang. The Shovel delayed me for a while but the Trumpet's Boots are on order now so I can get it on it's feet next week.

 

what kind of 750 barrels? T140?

is that why youre making up head steadies?

 

@speedrattle they are Routt 9 hole big bore barrels.
The head bolts are like that as they are all I have for now. They were taken off of another bike I dismantled and originally held the coils. I'll revert to the original steady and bolts when I order the parts.

 

the 750 jugs on the long rod motors work really well

 

You can't beat a nice pair of jugs.

 

those appear more like an 850 kit

 

Built one for a mate years back, with porting, cam timing altering, and new carbs it did indeed, " work really well " !
I vaguely remember Americans not liking the 'short rod ' 750 for flattrack racing, for some reason ?

 

Built one for a mate years back, with porting, cam timing altering, and new carbs it did indeed, " work really well " !
I vaguely remember Americans not liking the 'short rod ' 750 for flattrack racing, for some reason ?

 

do you recall the cam timing you used?

 

Some note you might not have https://www.tioc.org/britbike/camshaft.pdf

 

https://www.thebonnevilleshop.com/c...cvl6vdaBZhMNXCHxPYOI2hy2VKvxcgLtnjsB-4zZ9fmYA

 

Brill - thanks for that. Hadn't seen that before.
From the days when magazines used to have useful stuff in them

 

they list the 750 short rod motor with a very retarded intake cam lobe center-- 111 degrees, with a more typical 103 degrees on the exhaust. as i understand it, that retarded intake timing was intended to de-tune the 750 so it wouldnt destroy its . . . one-piece timing side main bearing? i forget.

normal timing is generally at lobe centers of 100/100, or 102/103, or in that range.

im curious because i run my land speed race bike at 106/109, very retarded lobe centers, and it has very good power at both upper and lower rpms. but the cams are 0.375 lift and 296.5 duration.

im interested in building a motor with a bias to low-rpm horsepower for a sidecar tug, so im thinking about what i might be doing there.

 

Ramp cams as fitted to pre unit Triumphs are a consideration or use dot to dot on inlet instead of dot to line.

 

was the dot-to-dot timing characteristic of milder triumph motors? that would advance the intake cam 7.2 degrees over dot-to-dash.

at any rate, super mild tuning is what im looking for. im not expecting more than about 45 mph out of that machine, especially with a 17-tooth gearbox sprocket, so any power over 4000 rpm is wasted.

 

Dot to dot was the Thunderbird tune