Motovert RX125 - ZS160 conversion

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Gelousi

Gelousi

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Nov 5, 2015
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Tullamarine, Melbourne
Hi guys,

First time posting, i have just finished converting my rx to a zs160... first test ride was last night so far all good...

a few questions tho, what carb is idea for street use? leave the stock go a OKO 26 or 28?


Its currently stock i bought a pitster pro and swapped all the parts over. added a lighting coil and its super fun..

also what temps to these motors run at? last night was around 20 outside and the motor felt really hot just cruising at 80kms i might look into changing the front sprocket to get those revs down....


IMG_4804.JPG
 
Welcome to Minirider's

That look's pretty clean
What stator kit did you use on it ?

Make sure you drop in and say g'day in our Introduce yourself thread while you're here

I cant quite see your carby, is it a Keihin copy 26mm 27mm, 28mm or a 30mm, or a Molkt 26mm, 28mm ?

Molkt-

$_14.JPG


30mm-

250carby3_zpsb816ef9e.jpg


250carby1_zps45050bba.jpg


A round slide carby like the one's above will give you the best all round performance, smooth weaving through traffic and in the lower rev's etc
An OKO D Slide will be a bit more like an on/off switch best suited for MX track's etc, but it doesn't take long to get used to them anyway
They can be used anywhere though, and the top end performance make's it a lot more fun to ride.

If you are heading toward's an Oko, get the 26mm if you are happy with the 160's performance, if you want to up the cc's like fitting a 177cc/184cc kit then go for a PE28 Keihin roundslide or an Oko PWK28


Check out some of the other Motovert RX build thread's here too.

Cheer's, Craig
 
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Very nice looking rx mate. If your looking at further mods, a tb head and hi comp piston would be sooo sweet on that thing, with the biggest cam tb make lol. I wouldnt even go the bbk, I would stick to stock bore size and just add the tb piston and head for insane rpms. If this could happen in the future, go a 28mm carb ;) If your leaving it stock stick to the 26mm. The oko is the popular choice, due to price and performance, or your could go a genuine mikuni vm.
 
Thanks craig, the current carb is a Mikuni 26mm not sure if its a copy but ive added a photo aswell...


the stator i used was from blygo as seen on this link.

Magneto Stator Plate Flywheel Roller ZS 155cc 160cc PIT PRO Trail Dirt Bike | eBay

I think ill leave the carb for now get used the current power as its fun enough lifting one wheel off the lights haha!

I do think in the future ill go the tb head route as a lot of people seem to be doing this. If it raises the rpms does the CDI need to be changed in tearms of a rev limiter

Im just scared if i push more power how is the gearbox going to last?

IMG_4819.JPG
 
That carby is the china copy Mikuni 28/30mm when tuned they are a good all rounder
The gearbox should be pretty good, the weak part is the clutch basket, but the complete clutch is under $100 to replace anyway
And make sure you start it from just past tdc so you don't get kickback too
The cdi will be fine , there isnt any rev limiter in them either
 
I just did the same too my rx with the blygo stator aswell. I'm running the oko 26mm on mine. How much better do they go compared to the 125cc lolimage.jpg
 
Man it should come out stock with a 160 or 150 at least... that 125 is absolute rubbish cant even do 80kms hahaha... nice i just fitted up my bash plate i can see you cut off that last support where the stater motor goes through, i ended up bending mine into place, Also ive added the stock 125 exhaust as its going rwc next week already reg'd so hopefully theres no issues i have been getting it most rwc as possible. One thing im waiting on is the front sprocket cover which ive bought from ebay

ZS 155Z Engine Sprocket Cover FOR Zongshen 150 155 160cc GPX 155 PIT Dirt Bike | eBay

Much better with the OKO 26 compared to the stocker??

Also just done the valve clearance both were a little on the tight side, ive set intake to .003" and exhaust .004" is that right for the ZS motors? all the info i can find are on the YX only
IMG_4822.JPG
 
Gelousi said:
Man it should come out stock with a 160 or 150 at least... that 125 is absolute rubbish cant even do 80kms hahaha... nice i just fitted up my bash plate i can see you cut off that last support where the stater motor goes through, i ended up bending mine into place, Also ive added the stock 125 exhaust as its going rwc next week already reg'd so hopefully theres no issues i have been getting it most rwc as possible. One thing im waiting on is the front sprocket cover which ive bought from ebay

ZS 155Z Engine Sprocket Cover FOR Zongshen 150 155 160cc GPX 155 PIT Dirt Bike | eBay

Much better with the OKO 26 compared to the stocker??

Also just done the valve clearance both were a little on the tight side, ive set intake to .003" and exhaust .004" is that right for the ZS motors? all the info i can find are on the YX only
Click to expand...


The rx50s were a joke. I remember going around the block when i first got it maxing out at 40kmph and 20kmph going up a hill.

Not to sure how the oko performs to others because its the only carb ive used on it.... but it goes nice and has pretty fun top end power.

How did you fit the stock exhaust? i thought it wouldnt of fitted because of the klx style head on the z160
 
What no way!! i didn't even know they came out in a 50 haha i could imagine it being soo slow...

For now im not going to touch carb until i do the TB v2 head and possibly the bbk,

The exhaust just fit had to slightly bend it to full seal on the head lol, also it rubs on the clutch cable bracket but it will be fine just for RWC then ill put the other system on. Only thing its stupidly loud is there any good mufflers out there that isn't too loud and not as restrictive then the stock rx one?
 
my new exhaust only just clears the clutch bracket by 1mm. I know what your saying, mine is stupid loud.
 
After a bit more work on it I managed to put the pitster pro header pipe on with the motovert rx muffler, just had to flip it around the outlet on the muffler was the same diameter of the outlet from the header pipe... Fixed the clearance issue and hydraulic clutch on its way :)

Also threw the oko 24mm on that I had on the 125. Seems a lot more revvier that's with a 37 pilot and 100main jet,

The manifold pipe looked identical diameter as the oko 24mm

image.jpegimage.jpeg
 
You can quieten it down a bit easily enough if you need for reg etc,
Take the muffler off and slip a washer into the inlet side of the pipe with a smaller diameter than the pipe (16mm i/d or close) then slip the muffler onto the pipe and bolt it up.
 
Seem a little dear? They are 1300 from dhz arent they?
What carb will you run on it? That 24mm oko was a little small for a stock market 160 let alone a 190. Dont get me wrong, it will run with it if its jetted correctly, but you will be losing a little power, essentially choking the engine back by not letting it breathe to its full potential.
 
Something about the US dollar has gone up that's why the price went up, dhz is cheaper but I can't have it posted, going away next week and can't wait haha, defiantly won't be running the oko24 on the 190, I think the pe28 is the go, what's a good jet starting point with that sort of carb?

Also I had the oko as a spare from my 125 wanted to see the difference was actually better then the stock mikuni
 
Pe28 is nice on the 190s, start with a 45 pilot, may need a 50 so getting a pilot jet kit with that range of jets and main jet between 110 and 125.... most guys on here seem to run 125 or higher, however having ridden craigs 190 with the polini 28mm carb with 45 pilot and 110 main jet I believe the 190 responds better to a lower than recommended main jet. Got to love the age old jetting debate ;)
Doesnt really suprise me that the 160 ran better with the oko than the fakuni, imagine the 26mm oko ;)
 
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My 190 had the Polini PWK28 with #45 pilot and #110 main

The PE28 has a #42 pilot standard and a #125 main, so you might need a #45 pilot to try out,
If it has a hesitation or backfire's through the carby off idle when you blip the throttle remove the fuel bowl and swap the #45 pilot jet in.
Also while the fuel bowl is off check what height the emulsion tube has been set at in the factory, some have been set incorrectly.
This pic is borrowed from PM, it show's the correct height for the emulsion tube, just over 7mm from the carby base

attachment.php



The main jetting you really need to try out how it respond's with the standard #125 fitted.
If at wot, it reaches a point and wont rev out then the jetting is too lean, so fit the next jet size up.
If at wotf it rev's out but cough's and splutter's and even pop's out through the exhaust then it's too rich, try the next jet size down.

Once the pilot and main jet are sussed, then check the throttle response at 1/2 to 3/4 throttle
Same thing applies as the main jetting, if it lack's power and feel's flat then lower the clip on the needle notch to the 4th notch down, and try it again.
If it cough's and splutter's in that rev range then raise the needle clip one notch to the 2nd from top and try it again.
If you find it need's to go on the top notch the main jet is too big, if it runs best on the bottom notch then the main jet is too small.
Change the jet and put the needle clip back top the middle notch and try it out again.
Then adjust the idle mixture screw to get the best idle.

needle.gif




Then when you have it tuned take it out for a ride up a slight incline with the throttle held wide open in 3rd or 4th and shut the engine down pull in the clutch and roll to a stop.
Remove the spark plug and check the colour on the porcelain of the plug near the tip.
You want it to be a coffee colour, dark blackish show's up being too rich, white is too lean.
 
Very good information exactly what im after, I'm a two stroke person and have jetted all my bikes to suit my style of riding. Four strokes new to me although from what you have told me it's basically the same. Just the plug chop is sknethibg I never done before.., also where's good place to get the pe28 carb online or any local shops?

Thanks
 
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