mount-field racer

hey i got this a while back from a friend of my uncles, and decided to make it go FAST lol.

anyway, no pictures yet although i have a video up...

basically i've

redone the paint
striped the deck off
removed the rear axle, sprocket and chain for want of stronger axle with out diff
professional looking accelerator without any wires showing
moved chair farther back(cause im six foot and get cramp if its to far forward and i have to work the pedals)
added handle bars and direct steer (with about a 1/16 turn play in it

things i plan to do

get racing stripes
get a new muffler/exhaust (its tremendously loud)
small back sprocket and bigger front sprocket (from gearbox)
shift on the go
bigger wheels
fix play in the steering
make sure it can wheelie then add a wheelie bar
remove all the stupid wiring and put in a simplified version
add a bonnet over the engine to protect it
and i MIGHT re-do the front chassis so the seats lower to the ground and the entire thing is stretched out, allowing more weight at the front, so it wont flip for hill climbs...

shift on the go will be achieved by a clutch and a bike clutch, basicly ill make a smaller back pulley(smallest i can go) then swap the front for a near identical one (obviously bigger) with a built in clutch (can roll forward without the gearbox moving cause of the belt clutch underneath) and a live axle with a disc brake, the pulleys will remain stock size just now so i know the gearbox is going "stock" speed but putting out a higher ratio.

any comments are welcome and ideas are better! tell me what you think about the clutch and the "shift on the go" idea and the sprocket ratio after the gearbox, the back one is a 45 tooth sprocket and the fronts a 8 tooth changing to a 14 tooth

Cool, cant wait to see pics and/or video.

Sounds interesting- i wouldnt go smaller then 3" for a belt driven pulley - would slip or fall off too much. Make sure you do a lil prepping on the trans as well ( clean the nasty grease /oil out, put zerks or fresh oil in)- in speed applications, youll need a strong trans or itll up and break on you ( ive had it happen - luckily i was just revving up to take off, wasnt at speed).

Make sure the wheels are double nutted or drill a hole for a pin - you dont want your wheels falling off at 20 plus mph either.

Lowering the seating position is definitly a plus - on my MTD it handles sooo much better - i can whip that thing into a corner and lean off the fender - goes around nicely and feels 100% more stable.

hmm i cant really lower the seat b cause of the engine, although am now nurturing the thought of getting the front stripped and re-done as a dragster style thing!

Is this a tractor or a RER?
PICTURES!!!!

Any way to move it forward then? It sounds like a RER ... youll want it lower .

if by RER you mean rear engined then yes it is lol...

its sitting down at my uncles awaiting a new back sprocket, although i stripped a bike today and the free-wheel and sprockets might work, don't want to spend too much lol, ill get pictures nxt time im at my uncles in the mean time you can watch my video(which you seem to have not seen lol!) of the first start up and run;

https://www.youtube.com/user/bigbleuboy

i need to know where i can buy a sprocket and i hoped you could help me choose a ratio

the front tooth is 7 and the back is 45 stock





I have found a 13 or 14 tooth sprocket that has the same centre as the 7 tooth although there is no keyway, i want the 13/14 tooth sprocket on the front as i can get a shift on the go gearbox! (can move forward but not backwards and engages with the gearbox...although this will put the chain out of line kinda so i hope to add small spacers to the diff at the back! WILL THIS WORK?!?!?!?

i want a pretty fast gearing and i dont want to change the pulleys
A. because i have non spare
B. cause i dont want the gearbox going to fast, since its shift on the go i hope to achieve a high top speed, i plan to lower it some more and maybe re-do the front end to incorporate a lower seat...

PLEASE help as i cant find many sprockets online!!!

P.S i would also like the same bolt pattern so i dont need to ruin it by drilling more holes

If you dont over drive the gearbox a little bit, it will be alot of stress on the output shaft on the trans. If it were me, id gear up the pulley a lil bit then make up the rest with the sprocket change. But I've never done this before with chain drive, so it would be a learning experience for me as well...

yeh ill try to gear up the pulleys a little (the front is only a one inch pulley) although it looks bleak for the possibility of doing anything, because of not finding parts at all, eg back sprocket, cant find a smaller one with the same bolt pattern, and i cant find any pulleys that fit the shaft or the engine, what would you recommend i search for?

finally got round to taking some pictures, its not much cause it was taken really quick!
the front end is nearly done

and the rear is in bits ATM (please ignore the mess haven't needed to clean up yet)

this is the gearbox and the front sprocket.



here is some more pictures I took, this is my custom, matching throttle

and the new handle bars, going to have to change the direct steer, has a bit of play.


im sorry if the pictures dont work although you can right-click and open in a new tabs should work.

also I Still haven't managed to source a sprocket or any pulleys, im going to gear up the pulleys and then adjust the Sprockets if i can. unfortunately I dont have any ideas about the shift on the go other than cutting off the original (which is pretty nackard (stuffed) anyway) so i plan to buy another, stock although im not quite sure if the heat of the weld might seize the bearings or whatever is inside allowing is to free wheel forward, another unfortunate thing is that I will loose the reverse gear if i do this.

what do you think guys think? any recommendation's?

Thats the same type trans im possibly going to use for my wheelhorse( unless i can get my horizontal twin going).

You really dont have room to lower the seat- unless the gear box goes in front of it. If its possible try lowering the rear axle as well- itll handle tons better.

Could ask around our friends from over the pond?
Ive had a pulley sent to me before, shouldn't cost alot, and there really is bugger all over here.

yea thx man and yea if anyone has a pulley or sprocket's they are willing to sell/give then i am happy to accept.

anyway here are a few more pictures i took today.
my custom exhaust - EXTRA LOUD LOL

only kidding! this was a temporary exhaust to cut down on noise

my custom foot pedal

underneath it is put through a hole which moves with the pedal.

the bracket that holds it in place

this is why i have been sooooo busy, building a three car garage for my uncle, drew the plans myself!


ATM I just want it running again because there is some tempting mud beside the new garage that i want to go through....

New garage = lots of storage for cool stuff
Really do like the set up, planning to lower it?

no idea chunk! just faster really, which is failing bad at the moment!

It's lower it a bit,even if you just drop the front axle right up into the frame and weld it solid. Makes it alot more stable
Any luck with a pulley yet?
Try asking some of the UK racers where they get theirs from!

im going to recomend a theter kill switch and lowering it and a solid front end with kart spindles you don't want that tilt when your cornering