Can anyone get better shift drums for lifan 140cc

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epod

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Hi all, happy newyear. 2008 gave me 5 screwed 140 gearbox's to work on. My bikes and mates. Such a shame becuase otherwise these motors are so good. My worked 150 has just done the same thing, damaged shift forks dues to dodgy shift drum, causing 3rd gear to be unable to engage.
Do any guru's know where I can get hold of better shift drum sfift fork combo's for Lifan's. Has know if red baron or BBR KDX 4 speed shift drum will fit? Any hlp would be greatly appreciated.
Peace in 09 ride on.
 
'Aint got a clue on that one ... maybe someone over at Planet Minis might know ... It'd be great if Honda Nice shift forks fitted ... Some vendor is bound to at least sell spares but you never know with chinese motors ... Motovert OZ , Big50.com or DHZ might possibly know ... DHZ has trannies listed for $45 ...
 
...you could get a usual shiftdrum and forks and let them be DLC coated;) ...every knife factory can do this!!
 
Thanks, what is DCL coating

What is DCL coating. I can get shift forks easy enough but no luck with new shift drum. I believe some lifan shift drums are just made poorly. Has anyone had to same issue with a YX/GPX 150 or 160 motor. I am thinking the YX /GPX shift drums will fit in as it is also 4speed all up shift.
Ride on .
 
its short for Diamond Like Carbon and its a ceramic coating ....you may know it from the forklegs of a GXR1000R...!
But orig. Hondaforks will fit too but not the drums!
 
Great info Mr Mountain ... The Honda forks are most likely better than Lifan forks but they don't even appear to be hard chromed like XR forks are ... My XR's shift forks are over 34 years old and show near zero wear ...

Here's a PM thread showing an AHP tranny that has hard chromed shift forks ...
AHP 4 Speed Transmission Kit for Honda XR/CRF - Planet Minis

Diamond like Carbon :

Diamond-like carbon - Wikipedia, the free encyclopedia

Titanium nitride :

Titanium nitride - Wikipedia, the free encyclopedia
 
Cheers fella's

Thanks allot for the info, you guys are bloody legends. The ahp kit will fit imports, just means the shift drum is 1 down 3 up. Has anybody selling this setup in OZ i wonder? It a shame the dollar is so weak at the moment.
Peace all, ride on
 
Bugger, just realised that the honda kit is for clutch's on the main crank shaft not the gear shaft. I shall ring around to try and find a shift drum and forks in OZ that fit.
 
That AHP tranny is designed for a crank mounted clutch (non start in gear) ... note that the mainshaft has a spline with a circlip (XR 75/80/100 style) instead of Lifan/GPX/XY mainshaft clutch style that has a spline and a thread ... XR's have a mainshaft clutch that is held on by a circlip ... and they're super reliable ... I showed that thread because the shift forks were hard chromed ...

This ebay link shows a hard chromed Honda shift fork for a horizontal engine ... it just looks like silver spray paint but it is super hard and wear resistant ...

http://cgi.ebay.com/ebaymotors/Parts-Accessories___Honda-S90-CL90-CT110-ATC110-ATC125-Gear-Shift-Fork-RH_W0QQitemZ230313921238QQddnZPartsQ20Q26Q20AccessoriesQQddiZ2811QQcmdZViewItemQQptZMotorcycles_Parts_Accessories?hash=item230313921238&_trksid=p4506.c0.m245&_trkparms=72%3A543|65%3A12|39%3A1|240%3A1318
 
Genuine Honda forks are FORGED steel as well so they are tough and bend resistant ...
 
AHP has another kit listed as extreme gearbox for imports. It is a close ratio 4 speed made from harden cromoly compenents including gears, shafts, shift drum forks and kickstart mechanism.. It is expensive though at $329us. These kits have been around since jan last year, funny nobody is talking about them? Is anybody running this kit here in a lifan? Are these kits made in chiina? I have asked my friends at Akunar if they can put together a a 4 speed close ratio race proven gear set for me. Not sure if they will have a shift drum though. See link below for AHP kithttp://www.ahpminis.com/store/product_info.php?cPath=58&products_id=482&osCsid=9c53c29e44c4936e4a3711a1ddba0268
Ride on.
 
yx/gpx gear drums are differant from lifan so i'm told

i put lifan 140 bottom end in mine

there same the major breaky bit on all of them is the dog lugs they are piddley little crap things

i'm at the point where i'm looking at buying a tacky engine and runnin that in my china
but i'm not sure how much better that will be

but it doesnt cost that much for china gear drums
but it does take 3 hrs to pull engine out rebuild and re assemble
 
They were talking about the cooper extreme close ratio box on a Planet Minis thread a while back but it was deemed that the ratios are too close for a long stroke big bore motor used for motard or tarmac racing ... IF they solve a breakage problem then they are worth it ... They should be great for a dirt engine ... My XR75 has a close ratio 5 speed racing tranny conversion (4 speed model) and the tranny makes one hell of a difference ... I can't recall if it's a PK Racing tranny or a Yoshimura Racing tranny but it's bullet proof and has survived since 1976 with the everything still looking like new ... Some goon (joeschopshop) listed one on ebay US then pulled it from sale after the bids went over $1800 USD ... I paid $280 for mine new in '76 ... So as far as I'm concerned $329 USD for a close ratio tranny made of high grade steel is an excellent price ... Customs will slug you though because the total with postage will exceed $500 AUD ... Get 'em to send one in two packages ... One thing to check is that the kick starter shaft looks like one out of a non kick in gear motor ... they drive the gear shaft from inside the cases near the front chain sprocket side ... I'd say that's why they are saying they can be "modified" to fit most chinese engines ...
 
Sorry for the missinfo, but could'nt this gear set be run on the stock shafts?
Cheers.
 
The old XR75 must be a great engine. I had one myself in the 80's. It was a worked motor in a a Yamaha YZ80H frame. My dad sold it a few years back just before I got into pitbikes. I wish I still had that bike to play with, although we blew up the top end a few times trying to get more speed off the bottom end, but the gearbox was always perfect. They was a KTM 65 with a XR75 squeezed in at the Frankston SX last year. It ran well in the pack.
I think I am gona run an YX160 and keep the lifans in the shed till I can find a reasonably priced upgrade for the gearbox.
Cheers, ride on.
 
Did your father sell the YZXR75 on flea bay ?? I remember seeing one a few years back ... Yeah the '77 and up engines with the cam running in half alloy/half iron are nowhere NEAR as reliable as the '73 to '76 engines with the one piece removable iron tower ... The later XR80's and 100's without the slinger can be junked really quickly if the oil isn't changed regularly ... the cam running on the bare head created waaayy more heat ... that's why they had to increase the size of the fins on the '76 and up models ... The early models were basically a small speedway engine and they were built from higher grade metals ... As the years went on , Honda started to skimp on quality ... I can't understand why they altered the bullet proof original engine design ... maybe people were hanging onto their older bikes a bit too long and doing them up because they were so reliable ... so they weren't selling as many newer model bikes as they'd have liked to ...

As far as those Cooper trannies go ... You'd have to email AHP to see if they can be easily fitted to 140's and 150's and if they'll hold up to the torque ... I hate emailing shops ... they're usually vague and beat around the bush ...
 
... You'd have to email AHP to see if they can be easily fitted to 140's and 150's and if they'll hold up to the torque ... I hate emailing shops ... they're usually vague and beat around the bush ...
:p ..specially AHP...Mark is a nice guy ,but he never answers on emails:p
 
Bugger I just sent him an email, lets hope they reply.
I just email akunar as well. There tech man is pretty on it. I am hoping they can find me some other gears that will work fine for my worked 150. It seem to have a good shift drum it just brakes 2nd gear twice now within 10hours riding. I bloody goes like the worlds fastest indian though, thats why I want to build a good strong gearbox. The other motors 3 140's all have shift drum problems, so if anybody knows where I can get new shift drums that will fit please let me know.
Ride on
My old XR75 was a 76 I think because it was a steel tank twin shock used for flat track racing, where it ran on Methanol with the right jets. Then we brought it for modified MX in 1983 and had it till 98. Did a few of my younger years racing her. She put me on the podium many times. It rev'd that hard the con rod went through the top of the piston on one race day. My dad never sold it on Ebay though. I lucky kid got it for next to nothing cause my dad figured he was never going to have grand children to see riding the old girl. on the coast near Forster Tuncurry. I still love that bike.
Peace Ride on
 
Here's a pic of the good motor ... (a great example of the best place to run oil coolers from ... the case take off like they're using now on Lifans and YX's is far superior to head take off because the oil runs thru the cooler at a higher pressure)

JeffWardReplicaXRpic4.jpg


Pic of a PK Racing 5 speed ... the gears are only 7 mm wide to cut thru the oil and reduce friction ...

XR75PK5SPEED.jpg


Stock 5 speed from a later model XR75/80 ...

XR755SPEEDTRANSMISSION.jpg


Ported vs stock head ... the ported intake port is only 24 mm ... the same diameter as the outlet of a 22 mm Keihin carb ... I tried a 24 mm Mikuni off a TS 185 Suzuki but it was stumbly down low , went great in the mid range , then died in the ass if you gave it full throttle ... Limiting the slide lift fixed the top end problem but I never solved the Mikuni stumble (even with a Powroll 96 cc bore kit) ... I bought a brand new 22 mm Keihin and it brought the engine to life in a big way ... it went heaps better everywhere ... A guy in the US who is making all the old hot up parts is using 22 mm Mikunis ... so he's obviously found the same things to be true ...

shocheads008.jpg
 
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