DHZ 138 or is it.

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442

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i bought a dhz 138 and recently heard that they werent a true 138.is this true.if so can anyone help me out with where to go from here i terms of mods.
also any ideas on shock mods
 
Yeah mate it's true.

G'day mate you motor is stamped 138 but it is really 127. 54mm piston 14mm pin with a 55.5mm stroke. It is still an awsome motor, but can be improved. They can be bored out no worries and fitted with a 55.5mm piston, making it 134.2cc. Anything bigger is risky and requires stroker kits very expensive also. The DHZ 140cc have 55m piston 15mm pin with a 59mm stroke making 140.2cc.
I have a spare "High Speed is the brand" high compression dome top piston 55.5mm. with 14mm pin to suit your motor. I have one excactly the same. Just what you need. $100 delivered it's yours. That is what it cost me. You can get you barel bored out for about $40-$50. Send me a PM if your if your interested.
 
ohh thats gotta suck i heard people saying 138cc aren't 138's and that they were the 127. i didn't want to risk it and bought the 140cc dhz. now there is alot of room for building its gonna be huge.
 
Hey 442. The DHZ rear shock suffers from "under" damping on Rebound.ie After pushing down on the rear of the bike the back end springs up too quickly and kicks."not good when hitting some whoops or a sharp lip on a jump !!!!! [Say hello to your front mudguard] The shock can even spring back that hard it breaks the top or bottom shock eyelets .There are 2 ways to fix this.

1st ...Have the rear shock rebuilt and re-oiled with good quality 10w oil then re-gassed....
Ps The stock spring is fine if you are 50-80 kg
just dont wind the adjusting rings down with too much preload on the spring when re fitting.

2nd...Fit a better quality [more expensive]Fastace shock !!

Oh ! And dont worry the 140cc Motor is a sweet performer as is !!!

Cheers
 
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sounds prettygood.any chance you know where to get the machining done in sydney.thanks for the info
 
thanks for the tip thumpy but i was lucky enough to buy a the last dhz 138.his next shipment was 140s.yipee lucky me huh
 
Anything over 55mm Isn't risky and does not need a Stroker kit. You Can Bore to 57-58 VERY VERY Safe. 60mm Max.
 
i have a pitpro 138cc so is it really only 127cc?? if so i have a lifan 140cc bore an piston sitting in my room the piston is 54mm so will this bolt straight in an not put stress on my engine ?? any more info i need to put this on please let me know
 
what size will the piston be in my pp138cc ???

an if the 140cc can bolt straght up what do i have to do to the carby so it runs right
 
G'day mate you motor is stamped 138 but it is really 127. 54mm piston 14mm pin with a 55.5mm stroke. It is still an awsome motor, but can be improved. They can be bored out no worries and fitted with a 55.5mm piston, making it 134.2cc. Anything bigger is risky and requires stroker kits very expensive also. The DHZ 140cc have 55m piston 15mm pin with a 59mm stroke making 140.2cc.
I have a spare "High Speed is the brand" high compression dome top piston 55.5mm. with 14mm pin to suit your motor. I have one excactly the same. Just what you need. $100 delivered it's yours. That is what it cost me. You can get you barel bored out for about $40-$50. Send me a PM if your if your interested.
this does sound interesting.i was thinking of this mod and also the IRK and lightened oil slinger.would this affect the reliability of the bike greatly as i am not racing just riding my local track with mates but wouldnt mind a bit of extra roost.
 
Hey 442.Go the IRK definately.My ride has a 140cc Lifan engine with 30mm Mikuni carby and it roosts with my 85kg weight !!!.I re-bore/build engines for a living and I wouldnt bother boring the STD 140cc engine,unless you are riding as hard as Bubba Stewart !!!


Cheers Brian
 
Hey 442.Go the IRK definately.My ride has a 140cc Lifan engine with 30mm Mikuni carby and it roosts with my 85kg weight !!!.I re-bore/build engines for a living and I wouldnt bother boring the STD 140cc engine,unless you are riding as hard as Bubba Stewart !!!


Cheers Brian

but i have been led to believe my 138 is only a 127
 
i just put a irk on my 138 to be honest i havnt noticed a big difference maybe i have the timming wrong
 

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