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stoozo

Banned Wanker of the Century
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Well the bike came today. All seems pretty well in order....

Been through basically everything, will bleed the brakes tomorrow...the rear doesn't even really work :/ so it will need to be done. This is my major concern. There was a random spring washer in the bottom of the box...I thought oh no....then found the bolt I'm pretty sure it was from. DSC_0133.jpg


Geezs they're good at making mild bolt that look like hardened bolts in China...Sounds good ran it to the bottom of the drive and back but still a bit of work to do before its all solid and ready to go mainly the missing linkage nut. Really the welds dont look to bad and the frame is only really concerning in the part that its not tubular which is where that other one snapped...Ill sort something out with it!

Good to be back wrenching stuff...forgot how much I enjoy it! DSC_0128.jpg
 

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yeah it's missing a nut, M10 x1.25mm iirc ?
grab some Nylocs for it, those chinese locknuts are a only able to be undone/done up a couple of times.

looks like the same frame i used on my custom Orion
 
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Yeah no worries sounds good move it to the build page!

Cool I was just going to yank the bold out tomorrow and take it to the hardware shop on way home tomorrow and match it with a high tensile and nyloc!

May as well replace it. Yeah I did notice a few of those bolts were half stripped when they came out when I was loctighting stuff not overly inspiring. There was a spring lock washer I assume was between the nut and the linkage, at least I hope it was from that. I'm really hoping there is as many high tensile bolts sitting in my bike parts box as I remember....I think they are finally going to get used....
 
Will have a look....got a little fixated on this 'legality' issue...Swan Reach looks decent. I will try to get some info from the local council I think...seems to be them that 'own' the land that gets used the police just inforce whatever that is ;)
 
that bottom shocker bolt was a little bit of a pain to get out on my Orion.
i ended up having to undo the bolt under the swingarm to drop the link rods down and out of the way.
it helps if you have a bike stand, otherwise just throw a rope over a beam on your verandah or whatever, and make a loop to hook under your rear subframe to hold the rear up.

i've been cleaning up the back yard, and just dug out my old spare Orion frame
i'll get some pics of the places to watch out for cracks for you too.
 
Cheers that would be good! Probably need to do a little bit of work on the frame! Well...this top bolt....geeeeezus....worst SPOT EVER!!! The last nip....and the spanner slipped....this is cheap as plastic. If I have any problems Ill just cut the wires off and solder them together. I think that has to be the cheapest part on the bike...will explode the first time a rock hits it I think! DSC_0142.jpg

Got as much of it done as I think will be done today! Still need to do my valves and maybe play with the carby a bit. Not sure which is cold start but the choke definitely needs some tuning. Its running super rich but thats ok at this point, as its running in! Its in one major piece now. Bled the brakes front and rear today...now they actually WORK...Dot 4 seriously I swear they were full of water!

Looks good just went for another putt in the driveway and the chain tensioner bolt wound itself all the way in, and started rattling....better get some loctite on there....The only thing I havnt done yet is lube the chain....but Ill do that tomorrow before I go for a ride at the block! All looking good, what fun building a motorbike :D cant remember having this much non beer induced fun in a fair while! Thanks for all the help guys never would have got there without this forum!!! Not done just appreciating the help I was given so I do applaud you guys for that! Excellent call on the nylocks too....sure was an M10....
 
tdr's are not too bad... i had one... you guys do know that?
it survived water... water as in a channel lol... pulled her out... 2 kicks and fired right up :p
the only thing i can complain is... the seat.... you could feel the frame in-between you butt... sooooo painful... lol
 
so was that the key/ignition switch you hit with the spanner ?
if it breaks, you can just unplug it and the bike will still start and run etc.

can't have hit it too hard, there's no blood anywhere, lol
 
with it running rich with the choke, on those Keihin copy carbys you don't have to move the lever the full way, 3/4 movement should help it start cold.

have you set the mixtures yet ?

get the bike warmed up, choke off

now raise the idle speed up to about 1800,
then turn the mixture screw out 1/4 turn,if the rpms slow, turn it in 1/4 turn, then another 1/4 turn again
leave it to settle for 10 seconds or so in between adjustments.
listen for the engines' rpms to rise, until it gets to it's highest/smoothest point.
then adjust the mixture screw in or out again, but do it at 1/8 turn at a time now.

once you are happy it is at the highest/smoothest point, then you can drop the idle speed back down again to where you are happy with it.

then take the bike for a ride and note what it is doing, and at what throttle position


give it a few big blip revs, to see if there is any hesitation there.
if so it may need a bigger pilot jet, or a cheaper way is to drill it out the next size up.
i have a spare Pilot Jet here you can have, save drilling out yours.
 
Yeah I havn't used the choke yet it wouldnt start with it on, so something needs some adjustment.

I havnt actually looked much at the carby yet...or taken the air filter off to see what the choke is doing. Will have to have a look tomorrow and I'll go through that list mentioned above cheers!

Hoping to get out for a quick ride tomorrow so I'll have to get that all sorted before I go, the old boss is dropping passed so I can ride the block He should be able to help run through it with me. I'm good with chainsaw carbys but they are a little more simple....I guess I'll see how well the engine was set up from the factory when we do the valve clearances tomorrow and sort this carby out.

Ill take a photo of the carby tomorrow so you can point me in the right direction!
 
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jingke carbs are nothing special, if you want to get a bit more out of the bike, i'd get a genuine copy Mikuni 22/26mm carb like this:Carburetor 125cc Dirt PIT Bike Honda Mikuni 26mm PZ26 Carb | eBay
it will most likely come with #95main and #15 pilot. you'll most likely wan to get a #20 pilot for it though, but the main should be ok for a 125. my fury 250 has a jingke 30mm carb, its badly built, it even has a plastic slide!
 
yeah, i have 3 of them here. Jing KE, Sheng Wey and a Giao Guan

 
i reckon they are all about the same, and they are easy to tune

for a 125 engine, i think the china copy Mikuni 22/26mm is the best though,
only downside to it is the mixture screw, but you only need to play around with that till it's set up correctly.
the Mikuni is easier to get jets for too.
 
yeh, but once you get the mikunis dialed in they're fine. just replace the pilot with a #20 and you'll be all set !
 
Its definitely the one on the right! About to go through this carby list. Is that above info still good for tuning this carby?
 
what i wrote in post #10, will cover the mixture adjustment.

you might want to adjust your valves first too,
as the mixtures will need adjusting after doing the valve clearances.

then when both things are done you will be able to give thew bike a decent run and do a Spark Plug chop.
the colour of the insulator inside the Spark Plug will tell you how the engine is running
eg; a white insulator is too lean, tan/coffee coloured insulator is perfect, and dark/black insulator is too rich
so you will see if you need to change the Main jet for a bigger or smaller one,
or if you can adjust the Needle Clip up or down on the needle to fine tune it.

did you replace the Spark Plug?
it's a good idea to fit a brand new NGK C7HSA too, the china Plugs aren't too reliable.


you need to do a long run (slight incline if possible) holding it at wide open (full) throttle for 20 seconds in 3rd or 4th gear.
then turn it off, close the throttle, and come to a stop, then pull the spark plug out there and then and check the colour.

the perfect mixture of fuel/air will give you something around a tanish/coffee colour.


a spark plug has a specific heat range, C7HSA, so when it is running under load and at full throttle,
the plug will reach a certain temperature, and will it's start self cleaning stage, by burning that black fuel off the porcelain.




if you do a Spark Plug Chop,
and find it is still a dark colour on the porcelain,
then you may need to remove the slide out the top of the carby,
and then the needle from it, and remove the clip, and set the Needle clip to the top notch,
then refit it all and give it another WOT run and recheck the colour
 
this is a good video showing how to set the valve clearances,
but when you do it, set the inlet at .003" (.08mm), and the exhaust to .004"(.1mm)

[video=youtube;QJciyJRJh8Q]http://www.youtube.com/watch?v=QJciyJRJh8Q[/video]
 
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