Thread: chinese quad bike two stroke petrol mix

evening all .Son is getting a fairly old wee chinses quad bike in road for his daughter .

not sure of two stroke fuel mix for it .

tried25 ;1chainsaw mix -seems a tad rich .

any advice gladly accepted. 50cc motor.

High quality pre mix oil and 50 to 1 will be fine

My experience is three caps of oil in to a 3.5L tank of #90 fuel. You need to pay some attentions to it, and adjust your mixture.

sorry Black Rabbit me old mate that tis not good advice its the old " add some and ohh just a bit more attitude that seizes two strokes " they deserve clean fuel clean air clean spark plug - whats a cap ?? use a proper measuring jug and an oil that clearly states its for premix two stroke engines - 50-1 as our good mate 7mmsaum says will be fine - kotuku since younsters are involved I would clearly label the fuel can - I think it was NZ Safety used to sell a small (3in square ) heavy plastic blue tag clearly stating two stroke - I have one on my can of two stroke mix for my lawn mower- cable tie it on and all good - years of managing rural fire stores we took it a step further - with both two stroke and four stroke pumps we ran red cans for straight petrol in our four stroke engines and blue cans for two stroke - the tanks on the engines were color coded same way and even the 40 litre bulk containers were red or blue - every year all petrol was rolled around - the fire store left with fresh - the old went into vehicles or chainsaws - I ran a product called sta-bil in our two stroke - its a proper two stroke fuel conditioner that prevents two stroke from going off in storage - but dont run that in your lawn mower their carbs dont like it - you only need it if you are storing two stroke longer than say 6 months - really good in outboard motor tanks - I believe Yamaha sell a product very similar to put in their premix tanks -chainsaws fine - an old mate had a chainsaw lawn mower business - every two stroke that came in locked up he would take a fuel sample in a clear container - when the customer came in and moaned at the $2-500 bill for motor or at least new pistons and tried to tell him "nah I put oil in " he had the proof "nah no oil in there " be nice to your two stroke proper oil and a measure not just chuck some oil in and hope for best

I have a regime of specific petrol cans for my chainsaws as one is 50;1 the other 25;1(CLEARLY LABELLED) so no worries
In terms of safety only my son or myself will do the actual mix -even then he prefers i do it.Unlike chuck and hope -I carefully measure the oil before actual mixing!
will check out spark plug today.

top man well organised -and the young fella I don't doubt learning some really good skills - at least today the spark plugs are simply way better quality than say 30 years ago - so is the oil quality- what I have seen stop two strokes is a carbon bridge on the plug - a small bridge of carbon builds up on the plug and instead of sparking it simply doesn't function- sometimes associated with to rich running but not always - and dirty air cleaners stops them to - idjits leaning out the carb to try and get the motor to rev harder not kind on engine either

Use a decent synthetic 2 stroke oil at 50:1 or 40:1 if it makes you nervous.
25:1 was used way back in the day when oils were not as good and new engines came with silly tight tolerances.

I've run bikes all my life on 50/1 never had an issue.

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Originally Posted by kotuku

evening all .Son is getting a fairly old wee chinses quad bike in road for his daughter .

not sure of two stroke fuel mix for it .

tried25 ;1chainsaw mix -seems a tad rich .

any advice gladly accepted. 50cc motor.

Just picked up one of these for the kids, running it on 40:1 with not much issue so far. Bastard to start is the first thing I find. Needed to replace the drive setup and tighten everything right up, realign the steering and a few other jobs. The one remaining one is figure out how to pull the exhaust setup apart and repack or rebaffle it, the little fu**er is stupid loud. I mean deafening loud, stupid for such a tiny little engine.

This one appears to have been run on 25:1 and Greta's tears, it smokes like it's a 1920's sailor. Hoping it will burn cleaner after a bit more use...

without trying to tell grandma how to suck eggs...
our outboards start MUCH easier on 91 octane...but will run faster on 96 or 98 a mixture of 91 and 96 isnt a bad option...worth a crack nigel.

Originally Posted by Micky Duck

without trying to tell grandma how to suck eggs...
our outboards start MUCH easier on 91 octane...but will run faster on 96 or 98 a mixture of 91 and 96 isnt a bad option...worth a crack nigel.

Yeah could be worth a crack. I haven't done too much with it as yet, I've gotten it to the point where it's coughing and spluttering with the choke on but dies when the choke is rubbed with your finger let alone opened... Once it's warmed up it's fine, half a pull no choke but cold - bugger me. Possibly it's just a bit gungy somewhere and needs a thorough run to get everything going again, it's a similar type of carb to what we have on the 35cc blower so there really isn't anything in them to go wrong. If it starts on choke, it should run in theory but likely there is a slight blockage in one of the jets I'd think. I had a quick look through it when I was cleaning it out to unblock the fuel system and remove the kitten fluff out of it, thought I had sorted it but not as yet haha.

Sounds like a jet issue for sure , id doubt it has an accelerator pump.

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Temporary blockage I think, starting and running fine now apart from the sheer noise... I haven't done anything else to it after cleaning the carb and fuel shut off valve out apart from pull the starting cord 400 million times. As far as the noise, the exhaust system is full of puke and needs a damn good blowout - after it stops leaking Greta's tears all over the rear shock and ground I'll have a look at repacking the thing. I chucked in another baffle which helps a little but really needs a repacking. This is the issue with running them rich on oil, polluting the exhaust setup!

Also seems to have a slipping drive setup which needs a further look at, or a throttle thumb adjustment on the kid (might be related to the freaking noise and not wanting to keep it floored...). I suspect in the fullness of time i.e. very shortly a proper kids quad will need to be sourced.

So I got a rush of blood to the brain and had a look at repacking the muffler on this little quad, bugger the proper repacking stuff is expensive! $40 for the size I need... Nup.

$2.08 at New World gets a 3-pack of jumbo stainless pot scrubbers, I welded a small section of exhaust pipe in over the top of the existing tube to redirect the exhaust gas forward towards the inlet end of the muffler and packed a pot scrubber between the pipe and the case of the muffler. Drops the noise down to the same as a weedeater roughly, still need hearing protection of some form but not shattering the neighbourhood. Next issue is the clutch doesn't seem that happy, might have to have a look at that again.

Runs fine on 40:1 though for the OP...

Good idea No.3 I knew of a guy that wanted to repack the exhaust on his rotary, He worked at a place that had 2 lathes turning stainless shafts all day so he used the swaff from them instead. After repacking it a quick test drive around the block was in order, Unfortunately he didn't think to wash the cutting fluid off it first. When he got back to the workshop the whole block was fully enveloped in a cloud of white smoke with people everywhere trying to find the source, luckily he'd burnt off the worst of the oil and nobody noticed the little remaining smoke coming from his tailpipe.