The added duration gives more top end, easier starting, less low speed torque. The stiff springs are a must, or the valve float starts before the good power kicks in. Worthwhile purchase, especially if some head work and compression is planned. TB300 is a good compromise, with a bit shorter duration, more in the middle, less over-rev.

 

head work and compression? sorry Im new to engines, how do I find that? is it on your site?

 

lol... Sorry. I don't have all the combo's listed. Every build is unique, even if it takes a little more time. What are you wanting from the motor? Is it an early 140 with the cast iron cylinder, or later aluminum one? A high compression piston, maybe a size or two over, adds even more torque than the long-stroke 140 already has.



Cylinder head porting helps, as the displacement increases, to allow top-end breathing. Adding 1mm oversize valves, as well.



Feel free to contact me with the specifics, and I can set some thing up for you.



Terry

 

well Im thinking about it for the near future, do you know how much it would be for shipping If I decided to ship it for you to work on from canada?and the engine is 2 years old if that helps with the cylinder type

 

well Im thinking about it for the near future, do you know how much it would be for shipping If I decided to ship it for you to work on from canada?and the engine is 2 years old if that helps with the cylinder type

I think the postage gets silly, even though I'm under an hour South or East to hit Canadian soil. Aboot $100 most of the time, each way. If you can tackle the top-swap, with instruction, it would drop to $25 each direction for jug and head.

 

so you would port + polish the head? Im having trouble on your site and Im wondering how much (ball park estimate) will a cam shaft, head gasket and maybe 160 big bore kit be?

 

*sorry 146 bbk, and this race head cam shaft will fit my lifan head?TB Race Camshaft for Race Head

 

*sorry 146 bbk, and this race head cam shaft will fit my lifan head?TB Race Camshaft for Race Head

Yep, that's a good all-around cam. Well worth adding, especially if you increse compression and displacement.



Your 140 requires a different piston than what TB offers in their BBK's, but I stock the 15mm wrist pin versions as well.



Porting is a big help, again, when you add displacement, compression and cam.

 

so this means that the 146 kit wont work straight, but it will work if you swap in one of the 15 mm wrist pin?

 

and do the springs come with the camshaft?

 

If your 140 is the version with an 81mm tall jug, you need a 3mm spacer too.

Valve springs are not included with the TB cam. I stock OE Honda versions that are ideal for the application, for $30/set.

 

how do I know if it is an 81 mm tall jug

 

measure it lengthwise from footgasket to headgasket...

(length in inches is 81/25,4)



(And the camshaftgear has 28 teeth instead of the for the big mills more common 32 teeth)

 

is there a different number or sizes of bolt in the cam shaft gear? if that question makes sense

 

My jug is 3 1/4 inches Firepower

 

Let me google that for you

 

whoah never seen that before, yeah 82.55 mm

 

I use that google method for alot of conversions

 

yeh thanks that was pretty d0pe

 

This too

inch/mm CONVERSION CHART

 

so fire power could you pm me a price for all those parts-cam shaft, new valves if possible, and a big bore kit for my I think 82.55mm jug?

 

*sorry^ with the valve spings too

 

so fire power could you pm me a price for all those parts-cam shaft, new valves if possible, and a big bore kit for my I think 82.55mm jug?

Yep.

Cam-59

Springs-27

Sprocket-10

Valves, porting, seat cut-125

BBK w/spacer, 15mm pin-149

 

if I did the porting locally, what would be the difference in price? whats the seat cut?

 

Yep.

Cam-59

Springs-27

Sprocket-10

Valves, porting, seat cut-125

BBK w/spacer, 15mm pin-149

I am running this(or quite similar) setup and it makes good all around power for MX, loads of torque for blasting out of corners.