shifter gokart project

[robin]

i starting to properly fit my bike engin into a racing gokart frame
i am trying to do it on the cheep but have some problems

i plann to use the orignal sprocket caryer that came with the axel bit it is 5.823 inches across or or 147mm and i want to bolt a 34tooth 428 sprocket will it fit or would the chain hit the carryer ?

 

[robin]

the way i am mounting my brake caliper the bleed valve wont be at the top will this cause problems ?

 

[Russ2251]

Probably will. Air rises to top where bleeder should be.

 

[robin]

how can i tell if the sprocket will fit because i don't want to buy it because it might not work. could i bleed the break with the cart up ageist a wall or something?

 

[dpaxson]

someone correct me if im wrongm but having the bleeder on top shouldn't hurt anything. just put a piece of clear tubing or something on the caliper so you can see if there are bubbles in the fluid when you pump the brake.

 

[Russ2251]

could i bleed the break with the cart up ageist a wall or something?

If bleeder is on bottom, then kart would have to inverted to bleed out air. Pretty neat trick.

 

[Russ2251]

someone correct me if im wrongm but having the bleeder on top shouldn't hurt anything.

Problem is, bleeder is on bottom. Having bleeder on bottom flies in the face of logic.

 

[robin]

i will take pictures it might help

to keep the chain tight i was going to move the axel back but doing this would move the disk in relation to the caliper
could i make a 3rd sprocket or wheel and ajust that for correct tension

 

[Russ2251]

Is engine mount not slotted for chain adjust?

 

[robin]

the sprocket is my main priority atm how could i work out the diamiter ?

this is what i will be using

http://cgi.ebay.co.uk/HONDA-CG125-C...14&_trkparms=72:1683|66:4|65:12|39:1|240:1318

or should i just buy one of thes but i would still have to buy a new front sprocket and chain

http://cgi.ebay.co.uk/KART-428-SPLI...14&_trkparms=72:1683|66:4|65:12|39:1|240:1318

 

[robin]

Is engine mount not slotted for chain adjust?

i am using a 11 hp 5 speed bike engine i cant relay make an adjustable engine mount

also how could i calculate the top speed i have got the geer ratios

# Transmission Type - 5-speed constant mesh
# Primary Reduction - 3.333 (60/18)
# Gear Ratios - 1; 2.769 (36/13), 2; 1.722 (31/18), 3; 1.273 (28/22), 4; 1.042 (25/24), 5; 0.885 (23/26)

the output sprocket on the engine must be 14 or 15 and my wheels are 10inch-250mm diameter

then what ever sprockets i can fit to the axle i would like a top speed of about 55 with the engine at 9000 rpm

 

[Kaptain Krunch]

take the transmission gear ratio and multiply it by the chain drive gear ratio, then enter that in the speed calc with the proper tire diameter and other info. So for example in 5th you would have a .88:1 ratio, multiply that by the ratio of your chain sprockets, and there you go.

P.S i think you have the transmission ratios backwards, 36/13 is way to high for first, it must be 13/36.

 

[jr dragster T]

i am using a 11 hp 5 speed bike engine i cant relay make an adjustable engine mount

Think because you have 11 HP the motor will move in it's slots? Well guess what even my race car's motor mount is slotted.

 

[Russ2251]

I think I understand what he means here.
Similar to a motorcycle mount. To adjust motorcycle chain, rear wheel assembly must be adjusted rearward to take up slack.
I think I would have made an adjustable/slotted mounting plate mated to engine instead of bolting it directly to frame. Should be noted that any chain gains slack over time due to wear and does not actually stretch.

 

[BradenM]

Think because you have 11 HP the motor will move in it's slots? Well guess what even my race car's motor mount is slotted.

My GX140 needs 12 nuts, 4 of which are ny-lok, with loctite, otherwise it pulls itself backwards and my chain comes off. Without loctite, and with each bolt done up as tight as I can physically manage, it still pulls back.

 

[Russ2251]

and with each bolt done up as tight as I can physically manage, it still pulls back.

Should not ever happen.
Make sure everything is clean and free of oil/grease. Clean base of engine and engine mount with alcohol until rags no longer pick up any crap.
Just plain old 5/16x18 bolts with washers (1 top, 1 bottom) and keps nuts works for me. Nylocks can give up after one use and I do not recommend them for engine mounting.
Keps nut

 

[Kaptain Krunch]

Should not ever happen.
Make sure everything is clean and free of oil/grease. Clean base of engine and engine mount with alcohol until rags no longer pick up any crap.
Just plain old 5/16x18 bolts with washers (1 top, 1 bottom) and keps nuts works for me. Nylocks can give up after one use and I do not recommend them for engine mounting.
Keps nut

My 5hp tecumseh never budged with just 2 regular bolts and 2 regular washers, and i was flooring it and letting off the gas alot.

 

[Russ2251]

My L-B's are also 2 bolters and don't slip.

 

[robin]

Think because you have 11 HP the motor will move in it's slots? Well guess what even my race car's motor mount is slotted.

yes but (i think) your motor is bolted down from its base like a gx engine mine is mounted like a bike engine horizontal bolts if i wanted to mount it to the base it would have to fabricate a engine cradle then make a base plate for it to fit. extra hassle and more weight. i have welded mounts to the frame to hold the engine

i am going with a 14 front and a 26 rear sprocket that will give me a speed in 5th geer of about 52mph at 9000rpm i get valve float at about 11rpm so that will limit the top speed to about 65 if i get a long enough straight

i found this site is good for calculating speed and ratios http://www.technobots.co.uk/acatalog/Calculators.html

 

[robin]

my axel berings arived today thay are huge i need a sprocke an chain of ebay but the seller onleay takes papal any idears anyone ?