Is the engine in the pp 140xr better than dhz 140?

[pb performance]

@Cactus Jack
Well, Thanks for making me look like a dick head !! LOL LOL LOL.... or did I do that by myself .. HHMMM..

If you say that thats the way to do it then thats the way to do it.. as you have never let me down on your info before !!!

So I've changed my above post so that people don't get any confusion !

But yeah thats the way I've always kicked my bike and also my mates 140s and have never had an issue !! although My mates 140s does sometimes kick back but not that often really !! normally starts first kick..

I understand why my bike has no problem, being a 125cc with lower compression then the 140cc's...

Any way's, all try your way by going just past TDC on COMP stroke and see the difference..

 

[MasterSpoon]

try kick starting a 576cc single with a left hand kickstart @ 10:1 compression
I found out quickly to do it the way Cactus just explained

 

[Cactus Jack]

Hey PB ..... Your post wasn't there when I started typing my post . It was only there after I posted mine since I went off searching Planet Minis for a decent link on kick starting technique but couldn't find any ....... but at any rate , I didn't fault your post at all ...... I thought it was quite accurate . In fact it made me go into greater detail since both our posts were just about identical .....

I've read several posts that show that STOCK GPX Jialings have kick start gear and case breakage problems ...... I also know a guy in Arizona who said BOTH his near new GPX's felt like the kick gears were "slipping" and crunching and he was worried about them letting go ........

I'm not the one saying that stock standard Lifan 140's bust kick starter gears ...... it's other people .... mainly sellers of other types of engines who are saying it ........ one thing is for certain ...... NO kick starter mech breaks on its own ........ the NUT on the end of the kick lever is most likely the TRUE cause in the majority of cases .......

Incidentally ..... most Jap bikes run an auto decompressor or auto retard ignition system to prevent kick back damage ........ the ignition ******* for starting , then advances to normal after the engine starts . Points systems such as what early XR75's had ran a mechanical centrifugal advance plate on the flywheel which retarded the ignition for safe and easy start up . Early British 4 stroke singles had a mechanical ignition advance / retard plate that was rider operated via a cable activated by a lever on the handle bars . Most Chinese CDI's and IRK's are crude and have the ignition on advance at idle so when making the decision to fit one ...... don't blame it on Lifan if you trash your kicker mechanism ..... you're actually whingeing about your own ignorance .

Here's a Cactus Jack trick you could try ..... if you have a hi compression engine that kicks back ......... fit a press button kill switch and hold the button in until you're halfway thru a swift , hard kick ........ then let your finger off the button .........

I used that method to kick start a 500 cc 2 stroke that I used to own after the cable snapped on the auto decompressor (Yamaha SC 500 ~ 96 mm bore x 68.5 mm stroke) . Those things had a dodgy CDI system that was supposed to retard the timing for starting but played up and made them kick back like a mule plus gave them a "Jekyll and Hyde" powerband ...... I eventually fitted a manual lever and cable operated decompressor into the spare spark plug hole which made life a lot easier . Owning that thing made me take up weight training ........

 

[Le|Garage]

Here's a Cactus Jack trick you could try ..... if you have a hi compression engine that kicks back ......... fit a press button kill switch and hold the button in until you're halfway thru a swift , hard kick ........ then let your finger off the button .........

That's very interesting and clever! Never heard of something like that before! Might have to experiment in the future. Cheers

 

[pmc.21]

jeez, cactus jack you know ALOT about this whole engine situation!
good job mate

 

[coolmodee01]

hmmmmm
i know what i'm gumma do
yer throw a lifan 140 barrel and head on my jailing donk
i've been thinking about it for a while......
but i might just put the big valve head on the 125 with a race cam
then i can race 125class and still be competitive

whats you view on this man

 

[Cactus Jack]

I have always been lead to believe that Lifan 140's had a longer cylinder than 78 mm (the length of a 120 /125/138 BVH alloy cylinder) ........ on Planet Minis some reckon the 140's cylinders are 82 mm and some reckon it's 83 mm ..... but the 1P55FMJ engine I've got has a 78 mm tall cylinder

http://www.planetminis.com/f21/new-141cc-55-5-x-59-a-40739.html

In the case of a Jialing , I'd fit a Lifan 120 BVH and try one of those plated all alloy 146 big bore cylinder kits . Theoretically , they're better than sleeved alloy cylinders because the piston and cylinder expand at the same rates and the heat dissipation is superior , allowing for tighter piston to bore clearances without seizing ..... the thin sleeve in bored alloy cylinders could also distort under piston thrust at high rpm loading .....

Iron or steel is used in aircraft engines because it resists distorting or going out of round and grabbing onto the piston when it gets really hot or is under heavy loading ........ iron cylinders ALSO resist ballooning (barrelling) and ring leakage in high compression engines such as supercharged engines and diesels ....... they're also used in high revving Pro Stock race engines .

 

[pb performance]

I've read several posts that show that STOCK GPX Jialings have kick start gear and case breakage problems ...... I also know a guy in Arizona who said BOTH his near new GPX's felt like the kick gears were "slipping" and crunching and he was worried about them letting go ........

Yeah I've also read about the GPX/Jialing motors doing this !! I'm on my second Jialing motor now (First one lost a tooth on second gear after many, many hours of clutch less gear changing ) But neither have ever had a starter issue of any sort, touch wood...

MAN people must be harsh on there starters !!

 

[coolmodee01]

i like your thinking cactus
but i'd like to keep it as a 125 i think if i wanna go any faster i'll buy a big bike again
what's the valve size in the 125 lifan head conpared to the jailing and a question for the air flow guru legarage what would be the most suitable cam to run with that combo

i'm not looking for overall power but a higher and more sustainable rev range out of the 125

thanks for the info

from a moderator point of view this is one of those golden threads that are worth reading word for word it's good to see miniriders coming back to it's true form well done

later


p.s i've got 2 bikes the vert and me diafo 3v 110 and have never in nearly 4 years had a problem with any kickstart you guys are way to hard on em hey

 

[motoXXX]

thanks for that cactus and pb now i will always kick my bike over as you said

 

[MITTZ]

from a moderator point of view this is one of those golden threads that are worth reading word for word it's good to see miniriders coming back to it's true form well done

from ne1s point of view this is an awsome thread, its just so damn informative!!!!!

 

[Gureno]

agreed!!

out of my entire life riding i have never once considered the life of my kickstart gears. this have been one dom-e-nant thread

i have learnt so much. thankyou yoda

 

[Drew4Bikes]

Bit offtopic here but there seems to be some wise people in this thread so its a good place to ask . Whats the biggest engine i can fit into my 140XR and what are some good upgrades to help with the all round performance of the bike. Thanks in advance for anyones help.