Pit bike Christmas late present

[Jim Davey]

Ok, the official line is I bought it for the kids ok?
I picked this up on Tuesday.



It's 140cc,
a 4 speed manual box with clutch and proper suspension and brakes. Ok it's a Chinese rip-off of a Honda or Kawasaki but bang for buck I don't think it can be beaten.
The problem is I've bought it for the girlfriends two eldest boys to learn to ride on and it's just too powerful to let them loose on. It doesn't help matters that the previous owner was a tinkerer. He's played around with the carb and fitted a ridiculously hard to modulate 1/4 turn throttle which makes making steady progress at slow/manoeuvring speeds a very ticklish procedure. Cue lots of kangarooing which escalates as you get jerked back and forth grappling with the controls, popping mini wheelies that nobody would call intentional.
Snatchy disobedient throttle action aside thing is awesome once on the move and due to the low gearing and small wheels really piles on speed at an alarming rate (it's all relative, I've raced go karts, done many track days and raced Downhill MTB so I like to go fast but it's my first motorbike and the damn thing feels like a rocket to me) so much so that I've invested in a programmable ECU for it. Sounds expensive but at £20 plus postage I thought billy bargain, it's a straight swap for the original CDI unit but it has a neat feature, a potentiometer you can use to pre-set your own rev limiter, say half (5,000rpm) or less for safer learning of the bike but the really neat part is the remote switch you can mount on the bars or hide away behind a fairing that re-sets the limit to maximum for those that want full power (me, eventually).

It's not old, 2013 frame with an 8 hour old 2014 engine, not sure how many hours the frames done but I'm guessing it's seen some action. Having been owned by a lad it's got a bit of a random assortment of stripped and rusty fasteners and cable ties cut off ragged (my pet hate) and shoddy electrical connections all filled up with mud, so I've spent a few nights this week sorting out bits and pieces.
Last job is to put the throttle back to standard as that quick grip thing just has to go.
All up I'm impressed, I'm hoping to give it a blast this Sunday if I can find somewhere suitable.
I'll post up some pics if I'm not in the back of an ambulance.

 

[eSCHEn]

Proper job . Looks awesome fun Jim, super jealous!

 

[mr migwire]

looks like a nice wee bike for the money, 2 wheels is always great fun especially in the dirt....

 

[pedrobedro]

.All up I'm impressed, I'm hoping to give it a blast this Sunday if I can find somewhere suitable. I'll post up some pics if I'm not in the back of an ambulance.

That's what happened round here, where is somewhere suitable? Kids were riding them everywhere till the public got fed up and the police started seizing and crushing them. A friend rented a field for his kid and mates to ride in but the neighbours round the field got fed up of the noise and had it stopped. Keep the bike for yourself and register it, get them a pushbike each and leave engines till they are old enough to be legal or get well in with a remote farmer. I'm not down on motorbikes, I've had enough and still ride a Hornet, how old are the kids ?

 

[shed or dead]

Nice bike.

The old Yamaha PW80 used to have a washer inside the exhaust flange, where it met the engine, which restricted power but could be easily removed to allow full power after learning to ride. Was a 2 banger though so not sure how it would affect yours.

Have fun!

 

[Jim Davey]

14 and 16, the older one is pushing for a moped and we're having none of it. I'm happy for them to get their two wheeled fix off road though as an outright no often backfires later on.

 

[norlander]

popping mini wheelies that nobody would call intentional

Yeah, ok Jim, we believe you

 

[Robotstar5]

I used to run minibikes at fairs,shows etc. most were single gear auto's but one was a 5 speed semi-auto which we would put into first gear then remove the gearshift to prevent any high speed antics.

Funniest episode was a mother paid for her little lad but he could not balance and kept falling off, I said it's just like riding your pushbike, his answer was "but I can't ride a pushbike"

 

[roofman]

Looks like the chain is going to eat into the swingarm when jumping humps

 

[Jim Davey]

No really, they were proper crap wheelies, I'm useless at modulating the throttle and rear brake setup as it is.
Practice is needed!

 

[Jim Davey]

The chain always looks like that, there is a sacrificial nylon chain guard screwed to the swing arm.
Also it doesn't come so close when the bike has a rider sat on it.

 

[Paul99]

Do you get the dreaded front wheel wobble when flat out? Neighbours kids used to bring one up for me to fix occasionally and it felt so unstable it was dangerous but there was nothing wrong with mechanically. I've ridden bikes since I was 6 or 7yo on a PW50 up to a CR-250 that I finally got rid of a few years ago but that pit bike was by far the most dangerous thing I've ridden. My brother who still races most weekend through the summer said exactly the same thing when he had a go.

 

[Jim Davey]

I'll let you know this after this weekend, I've not got it out of 3 gear yet as I've no room to stretch its legs in works yard.
Hopefully I'll know more after the weekend.
I did put the yoke and bars forward a little as it felt very cramped and tended to make you sit quite far back on the bike (they are designed for kids though not 5'11" chubbers) and that's helped a little, but if you stand straight up on the pegs your very close to the bars which feels very unstable.
Ours is the big wheel version, so hopefully a bit more gyro effect and more stability? Time will tell.

 

[BuiltnotBought]

Is it a monster moto, looks similar to my old one? have you broken it yet?? The lads and myself have had many of these. Brilliant fun, but you spend as much if not more time fixing them than riding them. You should find that if you turn the throttle up just a touch on the adjuster (to take the slack out of the cable) you can up the revs ever so slightly and then there is no need to touch it at all. especially for them to learn on.
It also pays as you get more aggressive to upgrade the rear shock. they seem to fail for a past time, along with the bushes, but you can get quite substantial quad bike shocks which bolt straight in (or some of the down hill MTB shocks fit them too. My best budddyo had a Fox DH MTB shock in his and it was unreal how well it worked) and for "5'11" Chubbers" you may find it a help. if you need parts for them give me a shout. I have a few bits kicking around but have a few friends with bits and pieces kicking about, cant promise anything, but there is no harm in asking.
the other thing you can do is drop the 110 engine straight in... that would give a major power drop, or (on the off chance you have one just kicking about) a Honda C90 engine without the electric start goes straight in, and they are semi auto so you can have a hand held back brake which is a wicked bit of fun and a massive change in riding style.
haha and as for the 3rd gear bit... I recall, possibly, accidentally, riding it down the road next to a car to see how fast we could get it (as it has no clock obviously) and I wouldn't swear to it but I think it was around the 65mph mark. I would seriously recommend getting them motorcross boots and a good lid. the only way these should be ridden is hard and fast... and lots of time spent picking yourself up off of the floor.

defiantly worth the money though. makes me sad for having just sold mine now ... ebayyyy

 

[Jim Davey]

I went out to some local woods on Saturday and had a thoroughly good time with it. However it looks like it will be back up for sale soon as the kids Dad (I'm their step-father) won't allow them to ride it.
It seems unfair for me to go out using it when it was bought for them to learn and play on so it's going to have to go.
So if you want another one? I've sorted out all the electrics, serviced the carb, bled the brakes and replaced any missing fixings and put on a new throttle and grips. Very tidy fast little bike, I'd like to hang on to it but I know I'll start messing with it and loose money upgrading parts if I keep it.

 

[Jim Davey]

The kids dad relented and has allowed the eldest to use the bike, (younger one doesn't seem too bothered by this turn of events) so we headed out to Four Marks MX and off-road centre last Sunday. The bikes a blast but too small for me to feel stable on off-road. The air filter gets waterlogged too if you splash through puddles stalling out the bike and requiring a tedious dismantling process to clean out the cruddy water.
This has left me wanting to get out there again but on an adult size bike, maybe a 125 to learn on.
Smiles all round though and lots of muddy kit to wash after!

 

[BuiltnotBought]

The kids dad relented and has allowed the eldest to use the bike, (younger one doesn't seem too bothered by this turn of events) so we headed out to Four Marks MX and off-road centre last Sunday. The bikes a blast but too small for me to feel stable on off-road. The air filter gets waterlogged too if you splash through puddles stalling out the bike and requiring a tedious dismantling process to clean out the cruddy water.
This has left me wanting to get out there again but on an adult size bike, maybe a 125 to learn on.
Smiles all round though and lots of muddy kit to wash after!

Because I am sad, I tried to make a cover for the air filter. It did work quite well and didn't affect the inlet much at all. Pretty much just a h;af pipe around the front half of the intake to help deflect any water and mounted to the same place as the air filter with a slightly larger hose clip. Though its true, they really hate water.

How big are you? one of the lads up the road rides one, he much be 6'2" and weight the best part of 15 stone. just had my bike off of me because I needed some smash. but he has ridden them for years . though he does come from a motorcross back ground. have a look for a Yamaha DT 125 if you wanna get something a bit bigger. Not expensive but a substantially better quality bike ... though no way in hell going to go in the boot of a 106 like the pit bike does

 

[Jim Davey]

I'm not massive, I'm 5:11 and have a bit of a one pack lol but I just think I'd feel a lot more secure on a bike designed for grownups if you know what I mean?

Water wasn't so much of an issue this weekend but the bike was bogging down and fouling the plug a lot making it a bastard to start so I'm going to strip the carb and check the float height etc. as the fun of spending the best part of half a day swapping plugs out and waiting for them to dry was wearing a little thin by the afternoon

 

[armalites]

14 and 16, the older one is pushing for a moped and we're having none of it. I'm happy for them to get their two wheeled fix off road though as an outright no often backfires later on.

I had assumed you were going to say they were 8-9, At that age they should be fine.

I'm not massive, I'm 5:11 and have a bit of a one pack lol but I just think I'd feel a lot more secure on a bike designed for grownups if you know what I mean?

Water wasn't so much of an issue this weekend but the bike was bogging down and fouling the plug a lot making it a bastard to start so I'm going to strip the carb and check the float height etc. as the fun of spending the best part of half a day swapping plugs out and waiting for them to dry was wearing a little thin by the afternoon

You could try going up/down on the plug, my two have LT50 quads and the eldest's one would stop after a while because it was getting to hot as he was flat out. Went to a colder plug and no problems since. You probably need to go to a hotter plug if it's fouling, if the previous owner had been tinkering most likely put a cooler plug in because of the performance increase.

 

[HMB]

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