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Discussion Starter · #21 ·
P.s the main symptom of a cracked piston ring on a pocket bike engine is when the bike idles really weird. e.g speeds up then speeds down etc.
 

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Discussion Starter · #22 ·
also i have a question for nick or cam.

when i ride my blata the clutch engages at 8300 RPM but once the clutch engages it does a 1/2 foot wheelie :| i tryed puting a 10 pound weight at the front of the bike but the front tire still lifts up. any ideas? i have wiped out atleast 10 times because of this
 

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hmmm....

Even I have to lean way forwards, (around 200lbs) is it the stock carburetor? or an upgraded one?

For the little ones (they are 16 now) we did drop the engagement point to about 6100 RPM, the engine should make much less power at 6000 compared to 8500, the powerband is silly on the c1's, something like 45% engine power around 4000rpm and 60% up at 6000rpms then it jumps up right around 8000rpms...

too loose on the clutch springs will allow it to slip too much, maybe try to fit a 2-shoe from a blata engine, but make sure it will fit whichever clutch bell you have (76mm or 78mm etc)
 

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But who prays for Satan?
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Hey Perfect, it just hit me like a ton of bricks, what front pinion are you running? if it's the stock 6-tooth, get you a 7-tooth, more top speed, less low end power, that would help keep that wheel on the ground coming out of those tight corners!

You could do less teeth on the rear sprocket too, that is the same thing as more teeth on the front pinion... I think 76t or 78t was stock, so you could step down a few sizes, but rear sprocket changes can *sometimes* change what length the chain will need to be, and are less noticeable per tooth, we are talking close to 70 teeth vs 6 or 7, so remember to add a X10 modifier for the front pinion change (speed / power wise)

Nick.
 

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also i have a question for nick or cam.

when i ride my blata the clutch engages at 8300 RPM but once the clutch engages it does a 1/2 foot wheelie :| i tryed puting a 10 pound weight at the front of the bike but the front tire still lifts up. any ideas? i have wiped out atleast 10 times because of this
My Polini did the same thing when I got it...............The problem was due to a single pad engaging the clutchbell only because the other two were sticky/oxidized..................I removed the shoes,cleaned up the shoulder bolts,,anti-seized them and re-installed with a new clutch pad set/springs and the ride got tamer..........
 

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But who prays for Satan?
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I like it, we do this for automotive brakes, that don't pull together all the time!

Plus, $0 is much easier to come up with than $25 and you wont have to wait for shipping! :thumbsup::p:thumbsup:

My Polini did the same thing when I got it...............The problem was due to a single pad engaging the clutchbell only because the other two were sticky/oxidized..................I removed the shoes,cleaned up the shoulder bolts,,anti-seized them and re-installed with a new clutch pad set/springs and the ride got tamer..........
 

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Hello PBP members!

For the past 2 weeks i conducted a little experiment. I'm sure that you have all heard of how to coorectly break in a pocket bike but i have come to with some surprising results.

I bought 2 Giovanni pocket bikes from ebay and my plan was to "break in" the engine with the "proper" method, which is not hitting high RPMs.
Then i was going to use my method which was to "ride it like you stole it" (KINDA)

Lets get started.

For the first bike i did everything by the manual. I went through 4 tanks of gas and i didn't hit high RPMs at all. (As the guide stated). Of course i heat cycled the engine first before hitting the track.

My second bike i did things my way. I started the bike for the first time and let it idle for about 10 minutes to get the gas flowing. I then took it out to the track and brought 2 L of petrol with me. My goal was to hit different RPMS. what i would do was go WOT then once it hit max RPM i would drop it down to a more idle speed. i then would go around the track going all different speeds. Mostly 3/4 throttle. Then once i burned thru a tank i put in another litre then i drove it like i stole it.

You might ask why i broke it in at such high RPMS.
Inside the engine there is a piston, there is also a piston ring that needs to be "set" properly. If you dont drive the bike in high RPMs the piston ring will never really get enough pressure to "set.

OK OK one thing you shouldn't do is drive it at MAX RPM for longer then 3-4 seconds as the oil in the gas has not et lubricated the engine. after one tank of gas the engine should be all lubed up. then you can drive it "hard".

Never drive your bike slow to break it in. you will lose alot of possible engine speed. In short words, do little burts of speed randomly for atleast half a tank of gas.

One other thing that is important is to let the engine warm up!

ALWAYS let your engine warm up before you ride it. (idle it for 5 minutes)


So how can i prove this?

After i broke both bikes in i hit up my school race track. (not one for cars and bikes but for people running lol).

I have a TOMTOM gps that shows the speed you are going and i was getting about 35 KMPH on the engine that i broke in with the "proper" way. As for the "Drive it like you stole it" method i was getting 47 KMPH.

I spent over 5 hours testing this method doing over 90 runs for 300 Meters.

I then took apart the engine and looked inside the "proper" way had alot of gunk inside that built up during the "break in" period. As for the "DILYSI" (drive it like you stole it) method it was completly clean and looked great.

I used the EXACT same bikes. Exact same parts. Exact same oil to gas for break in and exact same tire pressure.

The only difference was how i broke it in.

So in other words guys... Drive it like you stole it! (KINDA)

Dont drive it to slow but dont drive it to fast for long periods of times.

Also just a random tip if anyone has hot exhaust problems.

On my blata B1 REP i had a Terrible exhaust problem it heated up so much that it would burn my ***. So what i did was get tin foil and wrap the pipe in it about 5 times, i then put a bunch under the seat and wrapped the gas tank. it helped TONS. try it :)
Tried this break in method and now my bike runs like s***!!! I should have just stuck with the manuals directions.
 

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My method is in between both of his. Also, the bike needs to constantly be retuned, especially during breakin.
 

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My method is in between both of his. Also, the bike needs to constantly be retuned, especially during breakin.
Nobody said anything about tuning (doesnt even say in the manual) so what would be the position for the screw when doing break in half in or 3/4 out?
 

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What's your poison? Mine is 40:1
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I honestly cant tell you. Your elevation and weather is different than mine.
Do you have a blata b1 or a chinese bike?
You need a base tune and then need to read your spark plug after a few runs, and retune when necessary.
If you have a Chinese cag motor with stock slide carb, I can help more. A w/c blata I wont know the stock settings, but after that tuning is the same. The spark plug needs to be looked at and adjust accordingly. Too lean, too rich, just right, etc
 

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It started off as rich i then cleaned it up and done the air and fuel screw (its a chinese engine and the screw goes clockwise to lean and counter clockwise to richen up the fuel) so that was that done but it runs like garbage after 4 temp syncs for the motor
 

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Nobody said anything about tuning (doesnt even say in the manual) so what would be the position for the screw when doing break in half in or 3/4 out?
More than likely you will have to rejet it for your altitude air density temperature weather and other atmospheric conditions play a huge part in it.
 

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Great (NOT!) That all i need more expenses first my bike didnt break in right due to the so called "racer break in method" second the immobilizer get ripped off by my nephew (who thought it was funny til i got hold of him!) And now i have to rejet/upjet my bike? FFS MAN! SCREW IT IM GETTING A PROPER BIKE!!!!
 

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Great (NOT!) That all i need more expenses first my bike didnt break in right due to the so called "racer break in method" second the immobilizer get ripped off by my nephew (who thought it was funny til i got hold of him!) And now i have to rejet/upjet my bike? FFS MAN! SCREW IT IM GETTING A PROPER BIKE!!!!
I can tell you this it is not the break in process you used you can basically put 40:1 gas into them and not even break them in and they will run fine ( not recommended )

All pocket bikes are 80% work and 20% play even the expensive Euro bikes are this way this sounds like it is NOT the hobby for you...
 

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Great (NOT!) That all i need more expenses first my bike didnt break in right due to the so called "racer break in method" second the immobilizer get ripped off by my nephew (who thought it was funny til i got hold of him!) And now i have to rejet/upjet my bike? FFS MAN! SCREW IT IM GETTING A PROPER BIKE!!!!
A proper bike??? All engines especially Two Strokes need to be tuned properly and tuned all the time unless you have fuel injection. If anybody told you otherwise they were wrong. Breaking in is really not that hard and it really doesn't matter how.
We are not getting all the information from you that we need to help you. Rejetting is cheap on a Chinese engine, if you have a slide carburetor, that screw on the side is an idle screw not a rich or lean screw. Send us a picture of your engine and carburetor and we can get you started off, and then you're going to have to take it from there by watching your spark plug. That will tell you everything you need to know about your engine.
And if you have too much oil in your fuel it will not run well either. There are so many factors that can make an engine run poor.
 

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Well he is gone, changed his name too. Perfect example of someone that should either not be in the sport or needs a personal mechanic. What he thought was a rich/lean screw was the idle screw.
 

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Well he is gone, changed his name too. Perfect example of someone that should either not be in the sport or needs a personal mechanic. What he thought was a rich/lean screw was the idle screw.
Could have been something really simple as well like he may have put two stroke fuel into a 40cc four-stroke bike
 
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