my 125cc shifter kart project

[justang90]

ok tomorow i will have the time to make some close up pic of my brake and the parts of the engine mount that come with with my kart.. and by the way like said earlier i have paid the frame 120$ and it comme with 4 rimed brand new slick tire, 4 used and cracked wet tire on rims and of course all the bolt and hardware but yesterday i have sold the 4 used wet tire with the rim for 80$ so now the frame cost me only 40$ !!

 

[justang90]

ok so..

on the first pic is the part i had with the kart

on the second pic is the braket i made to put the dirt bike caliper

i made some custom braket from 1/4" stainless plate for the master cylinder that was on the dirt bike handle.

has you can see i replace the tank so now it sit on the side pod bar.


im still waiting for the fuel pump and the sprocket...

 

[anderkart]

Kinda looks like your caliper is mounted a bit high and you wont be geting all the surface-area contact/ braking potental out of its pads. But it might work fine like that, and the rest of your brake system instalation looks awsome!

What brand/model of motorcycle brake parts are did you use?

Looks like you only got 1 clamp for a racekart motormount. I dont recignise that other aluminum thing with the 3 oval slots, but I dont think its part of any motormount Ive ever seen before. Meybe it's part of a caliper?

Theres some racekart style motormounts listed on ebay.ca:--> http://www.ebay.ca/sch/i.html?_nkw=...ormount&_osacat=0&_trksid=p3286.c0.m270.l1313
Your top plate bolted to one of those 5-degree models would probaly work great. If you check those sellers other items/autions, you might find they offer flat mounts too.

ps: dont forget to double check they'll fit your karts frame-rail spacing

 

[brandongeiger2]

When you get rid of the tank ill buy the cap it would look sick on my bike!

I'm with you ander about the caliper you won't get all the stopping power because its a floating caliper i would try and move the disk further to the left so you can move that caliper closer to its mounting point. Cool project though!

 

[justang90]

When you get rid of the tank ill buy the cap it would look sick on my bike!

I'm with you ander about the caliper you won't get all the stopping power because its a floating caliper i would try and move the disk further to the left so you can move that caliper closer to its mounting point. Cool project though!

the tank cap come with the bike and i was suprised how heavy it is loll.

you and ander you are right i will try to put the caliper lower on the disc because just like you said the caliper is floating a little and i was afraid of a brake failure under hard braking..

the pit bike that i have take appart its a ZSTAR 125cc chinese junk

 

[justang90]

ok i have some update !
i receive my part today and here is a pic of the mikuni fuel pump and the 21t sprocket

but guess what ? where is the chain ?! i didnt find it !
and the suzuki store in my town close to 5 tomorow i will buy a chain and forget the old chain that i cannot found
i will try to make a video (if the kart work without problem on the first try)

 

[brandongeiger2]

the tank cap come with the bike and i was suprised how heavy it is loll.

you and ander you are right i will try to put the caliper lower on the disc because just like you said the caliper is floating a little and i was afraid of a brake failure under hard braking..

the pit bike that i have take appart its a ZSTAR 125cc chinese junk

When I said floating I was talking about the type because its not bolted directly to a plate(Fixed caliper) your caliper is able to slide side to side so it doesn't bind if the rotor isn't perfectly set in the middle.
Also I used to have a billet cap it was quite heavy but its not a big deal plus it could bring a little life to my bike

 

[EvoDre]

nice once again another nice KART

 

[anderkart]

Your missing one of your cassette axle bearings. It would be best to have 2 bearings on the sprocket side, but If you want to ride the kart with just 1, you should move it to the outward position so it would be giving your axle much better support.

 

[justang90]

It was my next question lol

I was wondering if i can run the kart with only 2 cassette and if i bend the axle can i put a 40mm instead of my 30mm ? (40mm cassette of course)

 

[anderkart]

Yes, you could instal a 40mm or 50mm axle, but you'd have to replace all your axle-hubs/bearings and sprocket.

A 30mm axle is plenty strong for your engine. If you just moved that axle bearing over to the outward position, there wouldnt be much chance of bending the axle. But the second bearing would help keep the axle from flexing, so your chain-tension would remain more consistent while accelerating, hitting bumps and cornering.

The 2nd bearing would simply help keep your chain from flying off as the axle and karts frame flexes. Some karts have a lot of problems with chains flying off. That's also why I sugested you use a motor mount that allows you to very accurately adjust your chain tension

 

[justang90]

Ok so to be sure for the axle i have buy and put the 3rd bearing just like ander said. I have run the kart 3 time and it run perfect but im new in the karting world and im not sure about the strengh of a kart frame... Is this ok to dump the clutch and make hard shift and take off... For now with my gearing i have hit easily the top speed of 55 mph but i didnt put more than mid throttle. I didnt try to make a little wheel spin on take off but on youtube some people make donut ?

I just want to know how hard i can drive my kart without bend anything ? And how easy is to bend a frame when drive on the street with some little imperfaction ?

 

[CustomShifter]

Believe me your frame will be just fine they Are extremely strong

 

[justang90]

some update...

i have run my shifter kart several time for know and it can make donut and some drift.. i had some little problem with the weak mounting on the chinese engine (just craked the crank case nothing to worry ) so i repaired the engine with jb weld (cause of the unweldeble cheap white steel of the crank case) an it work great and i made a new mounting concept with steel and a piece of 2x4 between the cassette older and the engine (realy strong set up)

so know i didnt have any problem with the kart. it run great and i cant dump the clutch at 9000 rpm without any engine mount failure so i think is time for more power (not all time just a little push if you know what i mean )

so i was thinking of puting my 8 oz nos bottle on it and when i want to make a little drift or make a donut in 2nd gear it will not stall.. i was thinking of making a expension chamber with pvc between the air filter and the carb and inject the nitrous in that so the engine will eat nos instead of air but it will not be forced in the cylinder..

ps: i was thinking of putting nos just sometime and not more than 1-2 sec so dont tell me that its gonna explode on the first shop i have try this bottle on my lawn mower and it have just make some flame but 3 years later this mower continu to run every week.. and I KNOW that if i put a bigger engine i will get more power so dont waste a reply to say that plz.

 

[OzFab]

so i was thinking of puting my 8 oz nos bottle on it and when i want to make a little drift or make a donut in 2nd gear it will not stall.. i was thinking of making a expension chamber with pvc between the air filter and the carb and inject the nitrous in that so the engine will eat nos instead of air but it will not be forced in the cylinder..

Nos doesn't need to be force fed. Put simply, nos or nitrous oxide is a catalyst which makes the fuel burn hotter.

Your delivery system idea should work well but your internals will suffer in the long run.

ps: i was thinking of putting nos just sometime and not more than 1-2 sec so dont tell me that its gonna explode on the first shop i have try this bottle on my lawn mower and it have just make some flame but 3 years later this mower continu to run every week.. and I KNOW that if i put a bigger engine i will get more power so dont waste a reply to say that plz.

Nos never runs full time, only in short, timed bursts, usually around 8 - 10 seconds; any longer & you will be sweeping up your engine. I'm unsure whether you can adjust the valve to run shorter times, I'd have to look it up.

 

[justang90]

Thanks for your advice ! I wasnt scared for the engine cause im sure some little burst will not kill the engine on the first time but i was scared cause the engine is about 3 inch from my seat loll

 

[justang90]

How much hp gain can i expect from a 12hp 125cc when i put the nos burst ?

 

[OzFab]

Have a quick read of this. It may answer a few questions