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unit_mx

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FREE MODS!!!!!!!!!

Lets face it most guys who own a china are either a tightass or have actually little money to spend on their dirt scooter.After handing all your cash over to mr wong their on ebay or some other semi Australian citizen with a 3month visa your left with next to nothing in terms of cash in ya wallet so to gain the most out of your new pride and joy for basically zilch i've slapped up a few ways that i have learn't to do some topshelf mods that require little dosh.

THE LEVER PERCH BUSHING
PURPOSE: levers and lever perch's are the most commonly broken part on all motorcycle this is due to there vunrability to hitting the groud when crashing due ,they snap because the perch fails to spin move on the bar however factory teams have used a secret way to prevent this brakage from happening by using a works connection etc rotating bushing (costs around $40) or by using teflon plumbers tape

HOW TO DO IT:
1) If you dont already have the common teflon plumbers tape go down to bunnings and buy some for around $2 ,it looks like this:
http://www.fibreglast.com/images/contentimages/528.jpg

2)take of your clutch and/or your brake master cylinder/lever perch and wrap the tape around 5 or more times where your perch goes making sure the tape sticks ,then rub the tape once done so that it becomes smooth and bonds together.

3)put your perch back on ,fit it correctly.Put some thread or nut lock (loctite ,permatex) on the 2 bolts and tighten them up some there isn't a whole lot of freeplay but enough so that you can move the perch up and down on the bar.And woolah you have just made your self a sweet lever bushing

FACTORY LOOK CUT AWAY IGNITION COVER
PURPOSE:Most guys go out and buy a cutaway ignition cover cause it looks trick ,you can remove the front sprocket without removing the casing and you can clean out all the mud build up and shit easily.However rather than buying a new cover simply just get the old one and give it some time with the angle grinder

1)Take the ignition cover off the bike after the bike is clean.
2)See on the inside of the sprocket cover where there is a peice of metal seperating the sprocket cover from the rotor cover you will be cutting off the sprocket side
3)Get a hacksaw and cut ruffely off the sprocket cover making sure you have left all the bolt holes untouched
4)now angle grind the cut smooth running close to the rotor cover wall ,dont cut off the bracing though we file around this later
5)file the bit where you angle grinded smooth ,use a round file to get that half cirle look on the cover
6)sandpaper it really smooth then get a scouring pad and polish it up so that it looks factory ,now you have a sweet cover for nothing


LOCKWIRE YOUR GRIPS
PURPOSE:It is 100% essential to have total control of your bike when riding it and the things you hold onto called grips have a tendancy to sliparound called grip throttle ,it pisses everyone off so to prevent this is actually very very simple

1)remove the grip of you bar and throttle tube
2)clean surface
3)if you have a gay throttle like mine it will have raised bumps on the tube ,file and sand these down so its flush with the rest of the tube ,clean again
4)clean inside of grip
5)get some ya Mums ,sisters ,Wife's hairspray or spray adhesive and spray the inside of the grip and on the bar and a tiny bit on the throttle tube .Doing this will act like a grip glue and will be real easy to slide onto the bar.Allow 10 mins to slightly dry
6)Tool time.Grab your vice grips and tighten so they lock when squeezed in
7)Grab some soft wire ,copper wire or stainless wire 0.5mm thick or 0.75mm thick and cut it in 16cm in lenght (do this 4 times)
8)get one strand of wire and wrap it around the grip about 2cm (some grips have groves for the wire) in from the end of the grip twice making sure that both ends of the wire are at the bottom of the grip.make sure that the wire runs parrelel next to each other and does not cross over
9)now get your vice grips and clamp the two bits of wire together and pull the wire downwards and twist anti-clockwise till the wire is tight and there is no slipping
10)if the wire is tight around the grip cut the end of the wire where you twisted it with pliers ,try and cut as close to the bottom of the twist as possible
11)now with your pliers push the remaning twisted bit of the wire into the grip so that it is out of harms way
12)repeat process on both ends of the 2 grips.No more throttle grip for you

POLISH INTAKE MANIFOLD
PURPOSE:Australian Dirt Bike magazine said that this is a very effective mod for very little money or nothing at all .The purpose is to remove the rough castings left inside the intake mainfold by polishing to give a noticable change in throttle response without using a drell etc
1)Remove carby and bolts from the base of the intake manifold at the head of the engine
2)Put a clean rag over your engine head to stop shit gettin into your engine
3)measure the diameter of the engine head inlet and the manifold inlet part of the carby ,write it down as the we will port this out to match the two inlets
4)grab some 20grit sandpaper and get ya index finger in there and sand hard ,puting in a protected vice is the best way.
4)this will take along time to smooth out the castings and to match either end of the inlets but its worth it ,so be patient
5)Now once you have polished it with the sandpaper it should be almost silky smooth ,so now you get the scouring pad and make it silky smooth
6)Scrub clean with a mild detergent
7)get a cut up optical lens cleaning rag or similar add some metal polish to it and polish till its smoother than a babys bum
8)put all the carby and shit back on now and feel good that you have done something productive with ya life


*Under no circumstances am I reliable for any mishap that you or your bike may have caused during the process or after you have used these modifying techniques.Stop being a cat in other words.

THROTTLE FILTER
Aim: Prevents throttle stick when the grip is pushed against the throttle body and causes the throttle tube not to flick back. Also prevents gritt and dirt build up inside throttle body
1)Remove grip covering throttle tube , clean up throttle tube
2)Grab a sheet of course foam or foam where the poars are quite fine and place your grip flange (flaired out end of the grip -the big bit!) and trace around the flange with a permanent marker , Then cut out with scissors the foam disc you marked up
3) find the centre of the foam disc and put a dot on it with the permo. Grab your grip and measure the internal diameter of the inside of the grip where it slides on to the bar
4) Mark on your foam disc a line the length of the internal diameter but reduce the diameter by about 2-3mm, try and centre the line on the dot that marked the centre of the foam disc radius. Continue drawing a few more lines on the disc that are the length of the original line drawn on it so eventually you get a set of lines that can be joined to make a circle
5) fold this disc in half and cut the inner circle out
6) now slide that disc onto the throttle tube and leave a gap of about 2mm from the throttle body , then slide the grip back on - Your grip will now be prevented from sliding up the throttle tube and rubbing on the throttle body!

RAISE YOUR TANK 20MM AND REDUCE VIABRATION
Aim: Its a pain in the ass having to remove the tank to pull the carby slide cap off when you want to play with your needle clip position and your knee's viabrate like a lonley housewife due to your engine not being rubber mounted. Kill 2 birds with one stone by using rubber stoppers availible from bunnings that prevent these problems from occuring (cost: $3)
1) Remove plastics, seat and tank. Grab your cream/black/ white (what ever colour float your boat) rubber stoppers used to prevent your lounge /tables rubbing on your floor and drill a hole around 5mm wide in the centre of the bushing (or what ever size the threads are on your tank mount bolts!)
2) Check to see if your tank bolts can thread through the bushing hole. Then your in the money
3) Get 2 bolts that are 50% longer than your old bolts to accomidate the rise
4) grab some araldite or superglue and glue a washer onto the bottom of the bushing
5) place the bushing underneath your tank , bolts the tank back on and its all done
-You will notice fuel will run to your carb quicker due to the increase in elevation of the tank and you can run a more direct fuel line route and can pull your carb cap off!

Grind out that exhaust seem weld for better flow!!

Aim: If you ever take the exhaust header pipe ( the long silver pipe running into the engine head) of your bike and notice the seem weld near the mounting flange ( where it bolts to the head). These welds often stick out inside your pipe , if you stick your finger down there and run it near the welded seem you will feel the weld inside the pipe , this in turn blocks a proportion of the exhaust and restricts flow. What we are going to do is grind out the weld and polish it to improve gas flow = improved throttle response.
1) Locate the internal seem weld
2) Get the semi circle round file out ( flat one side , round the other) and get filing , file till most of the weld is grinded down
3) Get your sandpaper out and begin to smoothen out the weld which you filed
4) once most of the weld is gone and the surface is flush , get your scotchbrite scouring pad and polish her up
5) polish it up with some decent polish like cotton briteshine
6) get the hoover out and suck all the shavings out of the pipe and bolt it back on





IF ANYONE ELSE WOULD LIKE TO ADD THEIR FREE MODS PLEASE DO SO!!!
 
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Divy

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mod 1 (THE LEVER PERCH BUSHING) is a good mod to do ive done it in the past and with a few falls i only snapped the clutch lever once

mod 2 (FACTORY LOOK CUT AWAY IGNITION COVER) ive done it to my pitty its very easy to do if you have used a grinder before it looks good an like unitmx said it makes it easy to clean mud off from around the front sprocket an makes changing front sprockets very easy

mod 3 (LOCKWIRE YOUR GRIPS) i do it to all my bikes i reckonmend it

mod 4 (POLISH INTAKE MANIFOLD) i havnt done it to my pitty but i wanted to do it i just forgot lol so thanks unit for reminding me i might do it tomorrow or the day after

all 4 mods that unit mx posted are really good mods to do and are also very cheap to do

top post unit mx
 

kwikaz

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inlet port

yer top post unit one question though, how do i port the hole in the head with out gettn metal dust in there??:eek:
 

binking

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Well done unit mx. Some top tips for anybody that wants some inexpensive and easy to perform "mods"
 

kwikaz

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ragga jagg

yer i was thinking of that but i was hoping there was a more sure fire way of doing it , or should i say more technical way.. but i appriciate the reply all the same. yer a valuble asset to this forum cassa :D
 

unit_mx

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cheers boys ,got any more that ya know of? .lol tim i spent all that time and effort cutin my igntion cover to smash it the first ride .sweet
 

kwikaz

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invention

HEY guess what guys ive got a reall good1 for you all im very happy i actually got somthn to give back for once, i ask how to keep metal dust out of my inlet port on my head while i was match porting to the size i wanted, cassa suggested to put a rag in and then vacume out excess dust when finished as this a pritty good i dea i wanted somthn a little more fullproof, so i sat there and come up with this wait for it......you know the coke caps from 1.25 litre coke bottles well if you look under the cap there is this blue disk wich seals the lid when tight so what i did was pick the blue disk out and measured it and guess what its the freaking perfect size fits snug az a bug, so i put three just for good mesure and know when im finished honing out the inlet port i will vacume the excess dust out and i will be able to see if there is anymetal in there wich there wont be cause theres nothing too catch on as the edges are at a 45% angle on the walls ITS BEAUTIFULL TRY IT OUT YOU WILL SEE WHAT I MEAN.. hope this is of some use to all you fellow members ... :D tell me what you think of my monkey?? there is a before and after but the before is when it looked nice and after it has a new lifan 140cc and im spraying the tank..
 

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kwikaz

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no problem

no probs buddy its good to give somthn back for a change. :D
 

motoluver

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Good info... I haven't rode in weeks due to the weather being shit. Today I am tuning my carb. I have just put in the 105 main, needle clip in the middle position and the air screw 2 turns out. I am now going to go work on the intake manifold.... I'll let you guys know how my bike goes later tonight.;)
 

Cactus Jack

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This is a mad lookin' little bike :

 
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Mud_Skunk

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4)grab some 20grit sandpaper and get ya index finger in there and sand hard ,puting in a protected vice is the best way.
4)this will take along time to smooth out the castings and to match either end of the inlets but its worth it ,so be patient
5)Now once you have polished it with the sandpaper it should be almost silky smooth
Cheers for the tips, they're pretty cool.

I gotta ask... 20 grit sand paper??? thats VERY coarse, i could imagine it making anything almost silky smooth.

:)
 

minidirt

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200 grit... even that'd be a bit rough eh?

yeah the port matching is a goer, definately a good thing, as for polishing the inlet to a silky smooth finish i've allways been under the impression that it's better to leave areas between the carby and combustian chamber with a slightly rough finish, bit of edge turbulance and that to keep atomised fuel suspended in the air stream... anyway guess i was wrong, anyone confirm that for me?
 

Mack

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The walls of the inlet system and exhaust should be as uniform as possible, without any lips or protrusion, but with a rough and even finish. Any lip or deformation in the wall shape will cause a turbulent spot which causes a disruption to flow at greater port velocities. The roughened finish will not cause major disruption, but instead create a small and even surface turbulence at the port wall, which will basically keep the mix from separating and slowing at this point.
The best way i have heard it simply described is this: imagine the bonnet of a car whilst driving in the rain at 100kph. The droplets of water may only be traveling up the bonnet of your car at 1 kph or less. Why is this? They should be flying up the bonnet at close to 100 kph.
At the surface of a smooth object, the laminar air flow is slowed and has weird things going on. So imagine polished port walls as that shiny bonnet and the droplets of water as droplets of fuel separating from the air and slowly traveling up the port wall and upsetting the mixture strength, blend and speed.
I think motoman may have described this in this way, i can't remember where i read it, but it is a good way to help understand the principle. I finish all my inlet ports and manifolds with 80 grit rolls.

Now the exhaust can be polished, because there is no fuel separation to worry about and the exhaust gases are leaving the port under extreme pressure and at high velocity. Polishing here reduces the port surface area, therefore reducing heat pickup, plus it looks trick and impresses people!
 
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