Motorbike engine question

[ibrahim123]

Heya guys.
I have found a yamaha motorbike engine (manual transmission) that will go into my go kart and i have quite a few questions on how to set it up on the go kart:

1) What mechanism and how should i set up in order to be able to shift into 2nd, 3rd and 4th gear from the front of the go kart since it is normally being changed from the engine?
2) Is it expensive to set up?
3) Is it something realy complicated to do or simple?
4) Shall i use the same clutch as it is from the engine to the handle bar or is it possible to not use clutch and just shift gears only?
5) Is there anything else i should keep in mind if i am using a motorbike engine rather than a normal go kart engine?

Cheers all!

 

[GuyJ]

Well the gear leaver on the box is mounted horizontal BUT its on splines so you can adjust so if you unbolt the lever and place back on vertical and have a solid rod linkage from box to a lever also vertical where you can reach it and you will push for 1st then pull for 2nd 3rd and so on. A clutch can be fitted on the same lever using the set up of a bike using the clutch lever. Do you get what i mean?

 

[GuyJ]

Also what engine is it? As one brake on the back proberly wont be enough so i'd go for two

 

[ibrahim123]

I do get what you mean. But can i create something run it along fro mthe engine, because i might not be able to reach the leaver on the box if i do it the way you say and maybe jusst bring it next to the steering wheel or next to the seat so that shifting is easier?

 

[ibrahim123]

The engine i am not sure the bike is a yamaha just liek this one: http://www.google.com/imgres?imgurl...VsMMG&esq=1&page=1&ndsp=24&ved=1t:429,r:1,s:0

Dont knw if u can tell what engine it is.

 

[ibrahim123]

So it is a 250 CC engine (2.5hp)

 

[MacfarlaneRacers]

You really should have put this thread in the mini bikes section as its nothing to do with karts

 

[r97]

2.5hp???????? where did that come from, 250 will prob do that at idle! lol. i would believe you posted this thread twice in two sections. shifting, lever pivoted to frame, knob on one end (for your hand), hole in the other end. shift rod from engine shift lever to hole in shift lever up front, or you can make it slightly more complicated! lol, look at my post on this threads copy, then reply to it here

 

[GuyJ]

you attach a rod to the actual existing lever then to a new lever where you can reach it which as r97 said pivots on the frame

 

[devino246]

You really should have put this thread in the mini bikes section as its nothing to do with karts

Hes asking about a bike engine on a go kart so it is in the right place.

 

[Doc Sprocket]

Heya guys.
I have found a yamaha motorbike engine (manual transmission) that will go into my go kart and i have quite a few questions on how to set it up on the go kart:

1) What mechanism and how should i set up in order to be able to shift into 2nd, 3rd and 4th gear from the front of the go kart since it is normally being changed from the engine?
2) Is it expensive to set up?
3) Is it something realy complicated to do or simple?
4) Shall i use the same clutch as it is from the engine to the handle bar or is it possible to not use clutch and just shift gears only?
5) Is there anything else i should keep in mind if i am using a motorbike engine rather than a normal go kart engine?


Cheers all!

1)You need to fabricate a shift linkage. You're not expected to be able to reach the original shifter from the driver's seat. Picture in your mind what you would have to do to connect a shift lever up front to the original pedal mounted vertically.

2)Expensive? Not really. Takes more time than money

3)Complexity is a matter of your own ability. If you've got some fabricating skills, should be no problem. If you have to ask about the shift, you'll have problems

4)Clutch- Normally, people would set it up for foot control, you may run a hand clutch- your call. But I'm guessing by your questions that you've never driven something with a manual transmission before. You might want to look into that- cuz YES! you need the clutch.

5)Do lots of research, scour this forum and the 'net, and look at bike-engined karts before going any further. Something else worth knowing? Yes- a bike engine will produce a lot more power. Make sure your kart is well-built and structurally sound with high quality steering, brakes, bearings, etc. DO NOT cut corners during the build. Your butt will depend on it.

Macfarlane, did you not read his very first sentence?

 

[redsox985]

My thought was attach a piece of steel rod to a vertically turned shifter a few inches up with a nut so that it can pivot on the shifter arm. In the cockpit area, weld the rod to a vertical handle so it is a push pull system to shift. Push for down pull for up. The long rod is bendable and can be fed through guides to get it where it meds to be and it would be securely guided by drilled tabs on the frame.

 

[modelengineer]

That's a good idea, but instead of the 'vertical handle' which you push forward and back, why not have a vertical piece of steel as a lever, with a pivot at the bottom and the push-pull rod attached about half way up. That way you actually have a shift lever. That's pretty much how it is with my sidewinder but it has a second lever arm because it's weird and the engine is freaking massive (... well the gearbox is, anyway)

 

[bighead]

I will be using one like this. Push pull with two cables.

 

[brendonv]

I will be using one like this. Push pull with two cables.

For a novice it would be very hard to get something like that to work well. Lots of tweaking to get just right.

 

[fowler]

the version modelengineer described is easyest and if u own a drill and a cut off saw it is very simple.

i made one for a 250cc engine and it took 15 minutes.

as for the clutch u can use an accelorator cable outa a car as it is ussually long enough to reach the front. the cable will cost $3 proberly and has a loop on one end and nothing on the other.
use the bare end by putting a ball of solder on it so it will sit in the clutch actuator (the little lever on the engine) and use the loop end to secure it to a pedel at your feet

also simple and quick to do

some people use the lever off the motorbike and put it on the shifter lever, but the hand lever can be hard and filldly to use when driving. also if u have ever driven a car it is more natural to use a foot pedal

 

[Kaptain Krunch]

Solder on the end of a steel cable wont hold up for most clutch setups.

 

[HellSpawn]

Solder on the end of a steel cable wont hold up for most clutch setups.

Yeah, what I've done for making cable ends is machine a tiny little brass cylinder, drill two holes that intersect in the center and tap the hole on the side/end. Thataway you can get a setscrew in there.

Stick your cable through, tighten down the setscrew. (And solder the other side if you wish for extra strength.)

 

[r97]

you mean a cable barrel?

this is my "complicated" design, its prob not really needed(prob even slows down shifting), but i think its kinda cool. pivot on frame, rod going through pivot, arm welded to rod, shifting rod (supported like redsox said) through a hole in the arm welded to the pivot rod, end of pivot rod (or maybe on top) are two tabs with holes drilled in them, shifting arm (the one your hand goes on) has a hole drilled in it, a bolt goes though one of the tabs on the pivot, then through the shifting arm, then through the other tab to a nut, then you have a spring on this shifting arm so it wan'ts to swing to one side. this shifting arm sticks up through a metal box with slots on it that are in the right place so when you shift to a gear you pull the lever to one side, move it forward, and it swings into one of the notches. i have a simpler idea if you wan't to hear that one? bolt though frame, compression spring over bolt, shifting lever over bolt, nut, that goes in the same type of metal box as the first idea, and works in much the same way, would work good for an e-brake. i can make a sketch up if any one is interested/doesn't understand what in the world i am talking about, lol

 

[ibrahim123]

Thanks for the really good info guys. R97 i didnt get your last post at all. Is it easy for u to draw it or something to make it more understandable? Thanks!