Mini-quad 50cc 2 stroke to 110cc Lifan!

[T.E.D. Jordan]

Hi,

I know this isn't the perfect place for this build, but what the heck, see if anyones interested!

I've a couple miniquad chinese piece of crap things for fun for a few years. Mainly for little tracks we make here and there but moreso for when it ices over - they're too much fun!

Aside the awful welding, the plastics that dont fit and trying to stop the carbs sucking in dirt somehow these quads are still great fun!

So, I wanted to re-vamp my favourite early blata replica quad with a bit more power and better reliability, heres what I started with yesterday afternoon:

started by cutting the original engine mount plate out and the surrounding steelwork to try to massage the 110cc engine into place:

Its tight! But do-able:

Blocked the engine up into place to give me an Idea of ride Height and how to mount the engine:

Which led to me realising the easiest way would be to cut up a spare pitbike frame for its mounts:

This isnt going to be a thing of beauty by a long stretch of the imagination, I just want it done asap so I can go out on the ice when it arrives!!!

Yesterday/Monday I did some more work on the quad, I started by shaping the backbone piece I cut from the spare frame:

I had mitred and shaped the top of the backbone to match the angle the seat mounting flats ran at but I ended up just chopping that away as I dropped the engine a little further to gain more clearance for the carb.

I sat the engine back in place and marked areas that would intersect frame positions where I could tack the backbone into place:

The very back of the original back-bone happened to sit parallel to this rectangular section:

and the two brackets that came off the backbone for the top engine mount touched the insides of the quad frame:

After that, I took the engine and backbone back out to clean up the areas I'd weld to on the frame and the backbone. At the same time I took the opportunity to neaten up the backbone a little of all the original pieces that were on it that I wasn't going to use and wouldnt have access to cut off after. weight saving ftw lol. I was hoping to not have to remove the rear swing-arm assembly but in order to fully prep the area I had to ( no pics ). After that, I just put the engine back in place, and tack welded the back-bone in.

Left side:

Right Side:

Back:

Which left me with:

the engine is so easy to lift in and out, you just lift the quad over it roughly, then hand-ball it in:

So the couple hours I worked on it on monday, I achieved what I'd set out to do, and mount the engine. I've still to fully weld the pieces in, and I've a piece of angle to use to mount the backbone properly yet. I'll be working on it today (its 1a.m. here in the UK) in the afternoon so hopefully I'll start looking at the front of the frame and the footboards. I've ordered a new wiring loom, starter motor, carb spinner and a couple of other little bits which won't be here for a while yet anyway. I also need to find a decent, small battery to use and I'll get a new one.

Thought I'd take a couple pics of what this engine was spare from. Its been deleted from my original post ( again, not sure why? )

Jordan

 

[T.E.D. Jordan]

Sorry if this appears out of context, I took a few posts off another forum, and some of my posts are still awaiting approval on here - which is strange!!!

Jordan

 

[timeeh]

All right i'll write back just to be nice LOL Looks like youv'e put a fair bit of work into that, you got spikes for the ice stuff? Nice work too

 

[zorro]

That's pretty cool mate!! I've got 2 quads for the kids, both 110cc but also have a 125 motor to throw in the larger of the two when our eldest is a bit more confident.

I've got all sorts of issues with the rear axel tensioners bending and throwing the chain, I've managed to somewhat control it with plate steel but am sure will need to weld something up soon as the metal will be quite fatigued. Any ideas?

 

[T.E.D. Jordan]

All right i'll write back just to be nice LOL Looks like youv'e put a fair bit of work into that, you got spikes for the ice stuff? Nice work too

Thanks man lol!

No Spikes as of yet, its more fun with the weak ice we get just to slide about with very little grip. But I'll sort something out for spikes

That's pretty cool mate!! I've got 2 quads for the kids, both 110cc but also have a 125 motor to throw in the larger of the two when our eldest is a bit more confident.

I've got all sorts of issues with the rear axel tensioners bending and throwing the chain, I've managed to somewhat control it with plate steel but am sure will need to weld something up soon as the metal will be quite fatigued. Any ideas?

Cool man, got any pics? If you have a look, I ended up just adding to my above posts instead of waiting for the inbetween posts to be approved (??) Some of the photos show what I'm doing to beef my frame up for the axle mounts. Are they similar to yours?

Jordan

 

[zorro]

Sorry mate I can't see the pics yet, maybe need approving???

 

[rotn50]

Damn power to weight ratio will be insane, this thing is gonna slide like theres no tomorrow, well done mate. Hopefully these pics go up soon, cant wait to see the strengthening you did to the frame.

 

[T.E.D. Jordan]

Sorry mate I can't see the pics yet, maybe need approving???

Yeh, I think thats the case :/

Damn power to weight ratio will be insane, this thing is gonna slide like theres no tomorrow, well done mate. Hopefully these pics go up soon, cant wait to see the strengthening you did to the frame.

Thanks!

Jordan

 

[zorro]

This is how I currently have the one with chain issues, only issue is no matter what I do I can get the rear axel straight so always has a slight crab walk. I've got an idea to rectify it but being summer here in Australia the kids want to ride everyday so major surgery isn't on the cards for a bit

 

[rotn50]

This is how I currently have the one with chain issues, only issue is no matter what I do I can get the rear axel straight so always has a slight crab walk. I've got an idea to rectify it but being summer here in Australia the kids want to ride everyday so major surgery isn't on the cards for a bit

View attachment 7383

We get them imported from china with a bar like that already welded, the holes that the axle mounting bolts go thru are bigger than the bolts and i have found that you need to be pulling the swingarm into alignment while tightening the bolts, if you dont have tension by pulling on the swingarm when turning the bolts the tensioning of the bolts will turn it out of alignment, keeping the top two mounting boltsrelatively tight enough so it doesnt shift but not to tight that you cant adjust the chain tensioners. Ignore this dude if thats the way you already do it.:grinning-smiley-003

 

[zorro]

I need to fully remove the rear end to see what's going on. I get what you are saying and do similar however with the tensioners theoretically you should just be able to wind them in to set the axle alignment and then tighten the bolts.

The bolts though like you say don't hold enough tension and as a result the axle under load can move as the U shaped bar is weak and does no good to hold and pop off the chain goes.

 

[T.E.D. Jordan]

Hmmm,

who do I need to pm to see about getting my posts verified!?!

Jordan

 

[rotn50]

You can PM motorman(nick) about your prob, nick is the administrator.

 

[T.E.D. Jordan]

You can PM motorman(nick) about your prob, nick is the administrator.

Thanks man, will do!

Jordan

 

[T.E.D. Jordan]

Just checked back in here and my pics are finally approved on the first page - yay!

I'll post up some more updates:

Got some more done on the quad today, cut off and tidied up a few brackets/areas. Then I used some of the pitbike frame that was sitting in the scrap bin to reconnect the front of the lower frame back to the strongest part of the frame. It had to miss the engine so I used a small bend before a straight section back to the frame:

Close-up of how the welds turn out welding chinese metals :-/

Before I attacked the other side I triple checked the engine still cleared the new metalwork:

Great success! (You can just see the new startermotor) Then I continued on to the other side, and did the exact same:

Same story this side with the weld:

Quick test to check clearances again, I'm chuffed that the engine literally just drops in and out from underneath. Very handy at this stage before I make the exhaust and the footplate:

Last thing I did was to remove the spar left of the sprocket in this photo as it was going to clash with the running line of the chain, I'll replace it with a one that isn't shaped inward.

I'm waiting for a couple more little pieces to continue, but I'll hopefully get some more done tomorrow afternoon.

Jordan

 

[T.E.D. Jordan]

When I recieved the carb spinner I had no countersunk M6 allen head bolts, so I bought a few and came to fit them, but found that the countersinks weren't deep enough (chinese replica of a UK made piece - in my defense it was half the price lol):

The spinner lets the carb exit the frame nicely, right into airflow and infront of knees which is great:

View from the front:

Recieved the battery today, gave it a trickle charge overnight and it was reading a full 12v by this afternoon. Its only 5ah, but its sufficient enough for this for sure. Mostly I wanted as small a battery as possible:

My loom also turned up, doesnt look much in the photo but its actually a quality loom, made in the UK;

At this point I got the quad wired up - literally plugged in the stator wires, (thats stator yes), attached the earth to the engine, connected the starter to the coil and the lives/negative/earth to the battery. Switched ignition to live and the engine turned over, which is always satisfying. I was going to get back to some more fabrication work but I thought hell, why not and dug out a spark plug, connected the coil, found the fuel tank and attached it then fitted a spare exhaust and tried to fire it up....

It started! But then it quickly stopped and was rather smokey, I realised then it was two stroke petrol left in the tank and I'd probably fouled the plug and blocked the carb. Now I know its a running engine though which is a bonus.

So for the last couple of hours fiddling with this amongst other things I disconnected the wiring loom and got a look at my new rear axles clamps and how they'd work out. Heres an original clamp:

Very weak, they flex with standard power/weight, and they deform making it impossible to adjust the chain tension nicely. These offset bearing carriers rotate to tension the chain/align the axle with the frame:

The carriers are a bit damaged from having to slug on them over the last 4/5 years of me owning the quad and a collapsed bearing at one point, but they're perfectly useable. They have a 50mm clamping surface with flanges to prevent them from moving. To beef this up I've bought these:

50mm steel split clamps. They'll work in much the same way but obviously be much stronger. The carriers fit inside them:

and the lipped edge:

Heres an offering up to illustrate:

I had trimmed the sprocket guard previously but had forgotten to take a photo. It slides on/off as it would on a standard engine:

I finished up having a look at what exhaust to run. I'd like to use the spare I have from the big pitbike we have:

But mount it centrally between the plastics and the axle:

But I'll have to see, as space is really tight there and I may have to fit the battery there...

I'll get some more done tomorrow fingers crossed

Jordan

 

[T.E.D. Jordan]

Almost forgot, I threw the old plastics on just to see how things were fitting...

No trimming required Bonus!

Jordan

 

[T.E.D. Jordan]

Bit of progress again, solved some issues, which made some others arise. I suppose thats always the way with these things!

Figured out that .428 pitch chain would be best, as its a standard chain type for pitbikes, and drive sproclets are therefore available with for the engine with the correct spline in a multitude of sizes. But the deciding factor was that I could then use one of these that I found:

a split sprocket - this solved so many issues I knew I was going to have with getting drive to the back axle. The next problem was this:

Where the axle mounts to the sprocket/disc holder, there is a recess. This creates a problem, as I had planned to just turn the shaft down from 32.7mm to the required 30mm to fit the sprocket. That would also mean machining some of the shoulder away, to get the sprockets aligned, so I've had to get a new one made to suit. Heres the drawing I've sent:

So while I'm waiting on that I thought I'd modify the frame to take the battery.

Theres only really one place its going to be able to live and thats up front. As it wouldn't fit initially I flipped the front bumper and bolted it back to the front upside down to keep things together:

Front end cut off:

Front re-bent and welded back together in a different position to suit the battery depth.

threw everything back together before I left and chucked a single wheel off a midibike project behind the swingarm to see what it would be like....

hmmmmmm...

nahhhh!

Jordan

 

[T.E.D. Jordan]

Got my axle piece back friday, so assembled the rear axle set-up, the machined recess is shorter and staged, to suit the axle better and maintain as much 'meat' on the piece for strength:

Also had the appropriate slot m/c'd into the piece for the sprocket to clamp to:

Cleaned everything with brake and clutch and started assembly using new bolts, torqued to full capacity, with locktite high strength retainer. Bolted the axle thro first:

Same story with the brake disk:

Fitted with sprocket:

Yesterday afternoon I cut the old rear axle mountings off the quad frame and shaped the cut a little to suit the radius of the split clamps:

It then took me a good hour or so trying to find a way to reliably centre the axle to the frame, and in turn the front wheels. I ended up within 2mm which isn't as good as I'd have liked but the best I could've hoped for. I tacked the assembly in place to start, then removed the axle and the unthreaded sections of the split clamps were all that was left on the frame. Using a thick walled 50mm Dia tube to ensure both clamps stayed parallel I welded around both fully:

Couple pics of it assembled with the axle after:

That last pic was taken while the axle was spinning.

Thats now the biggest milestone out of the way, I have a footplate to make up, and an exhaust, and I want to shorten the loom otherwise I'll have a mile of useless wires to deal with. Typical that we get a bad week of snow/frost here in most of the country but right where i am!

Jordan

 

[T.E.D. Jordan]

I havn't updated this for a couple of weeks now. I havn't finished off the fab work yet, all thats left is the floorpan/footrests and the exhaust, but when I was looking at the frame the other day I saw that there was an area that could do with a bit of strengthening and it would double up as somewhere to mount the ignition, so I traced the area out and re-produced the shape in CAD (Cardboard aided design):

Traced the shape onto some 4mm plate I had, and cut it out. I also cut the hole for the ignition barrel at the same time:

Tack welded in place - checking the fairings will fit over the new stuff also:

Opposite side fully welded:

Threw everything together at that point and started the bike with a brand new carb and an oil change along with fresh fuel and a new spark plug and started the bike up, runs better without 2 stroke mixture petrol lol:

Jordan