help with headstem bearings

[drew 60]

hey i have a 138cc pitbike, and the bottom headstemm bearings need replacing but i cant find anyone anywere that sells or can get a hold of a new one, the bottom bearring is a different size to tha top one, it has been suggeseted that i get a different size bearing and machine sumfing to make it fit but i dunno, i hasnt been ridin for months and miss it, soo i neeed any help soon

 

[coolmodee01]

there silly the china man

the botton cup is a cross between a 320/20 and a 320/22x ther use the cup from one and a cone from the other

get hold of andy at big 50
even brian at east 50 might keep em where eva is more suited

good luck

 

[roost666]

the numbers you have stated above are for cup and cone complete brg if you know wat i mean.......32020 is a cup and cone and same with the 32022......

 

[Cactus Jack]

Most later model Chinese frames have steering head tubes and steering stems that take a 44 mm O/D x 22 mm I/D top bearing (CGZ 320/22) and a 44 mm O/D x 23.5 I/D bottom bearing (CGZ 320/23.5)

Hondas take a different size .. 41 mm O/D x 22.5 I/D top and 41 O/D x 24 I/D bottom ... as do Pimpit (TDR) KLX plastics frames ... and early model DHZ crf copy frames ....

I've bought sets of the chinese steering bearings from 3 different ebay sellers for $15 a pair ... DHZ is one , surf_babe001 is another and the other one is long gone ... It pays to buy a few spare sets and way on down the line you'll be glad you did ...

Well surf babe still has 'em ... $15 delivered ... You get a set with one (CGZ 320/22) and one (CGZ 320/23.5) in it ...

Brand New roller bearing set for TRILE CLAMPS 125c140cc - eBay, Other Cars, Bikes, Boats, Cars, Bikes, Boats. (end time 15-Oct-08 21:42:09 AEST)

 

[coolmodee01]

the numbers you have stated above are for cup and cone complete brg if you know wat i mean.......32020 is a cup and cone and same with the 32022......

yep thats right

the sizes as crazzy stated well on mine in particular top is 22.5id 41od
so the cone out of the 320/22xj and the cup from the 320/20 because it is narrower than the cone on the /22xj silly i know

but as crazzy says the sell the china brgs but you cannot get the sets in a jap quality brg without mix and matching

 

[Cactus Jack]

You can get the 320/22's in a Jap bearing (can't think of the brand just now) but you can't get the the 320/23.5's in Jap as far as I know ...

I have All Balls Jap CRF bearings and the 22.5 and 24 inners don't fit the 44 outers ... the Jap inners sink far too deep into the 44 O/D cones so the rollers protrude plus the taper angles appear to be different ... They'd stuff up quick smart ... like on the first hard bump ... And as you have stated the CRF bearings are also narrower from top to bottom compared to the Chinese bearings ...

You're best to run the bearings as they come .. no mixing and matching ... Just replace them as a set if they wear or develop problems ...

 

[drew 60]

yer thanks guys ill have a look around and see wat i can find

 

[roost666]

i have jap brgs on the shelf here at work but i tell u now they arnt 15 bucks each lol....they are a timken brand

 

[drew 60]

cactus jack, i went to ebay and have ordered a pair of those bearings from surf babe, jst waitin for them to turn up, hopefully these will work out for me, thanks for the help.

 

[Cactus Jack]

i have jap brgs on the shelf here at work but i tell u now they arnt 15 bucks each lol....they are a timken brand

Yes Timken used to be considered to be the best ... What sizes have you got them in ... 320/22 and 320/23.5 or 22.5H-41H and 24H-41H (All Balls KML) ... China calls their CRF sized bearings ... 91683/22.5 and 91683/24 (HRB) ?????

When I was an apprentice fitter machinist I had to do 6 months in the store where I learnt what's what about everything to do with bearings , nuts , bolts , cutters , tip tools , taps , dies etc etc .... One of the things they taught me was to get the numbers off stuffed bearings and match 'em to bearing charts ... Back then you could get Timken bearings for $4.00 each whereas motorcycle and automotive shops wanted upwards of $25 each for the same bearing ...

 

[drew 60]

hey i got those bearring off surbabe 001 today and put them in, also got a whole new exhaust, all that for 65$, great, finnally got to go ridin for tha first time in weeks

 

[Cactus Jack]

Great news dude ... good on ya' ... I just bought two more sets off them myself ...

 

[roost666]

if u guys need brgs, seals loctite i can source for ya but i have no chinese ****** brgs all jap as i work in a brg shop and can post to u guys for 5-10 bucks

 

[coolmodee01]

mister mitchel weber wont like that new inenco freight policy there bro

bloody skf distributors he he he

have you nutted out that head stem combo yet i've been on the road so i havn't had time to do the research bloody life of a rep

 

[Cactus Jack]

if u guys need brgs, seals loctite i can source for ya but i have no chinese ****** brgs all jap as i work in a brg shop and can post to u guys for 5-10 bucks

I've been to bearing shops bro' and they've NEVER got what you want ... On top of that most of the guys working behind the counter haven't got the skills to think for themselves to be able to come up with a workable compromise like they did in the good old days ... They're chart and numbers or computer boys ... most of them can't use a set of verniers or mics to work out bearing sizes and know things in their heads ... just like most of the goons working behind the counters at bike shops ... I actually sent my missus to a bike shop with a set of brand new Loncin valve stem seals in a satchel as a sample to match with and they didn't have the brains to know that CRF or CT seals are the same ... That's the equivalent of sending someone to an engineering or hardware store with an unmarked 5/16 drill bit and they can't match it because it has no numbers on it ... they want the customer to do their job for them ... I'll bet that if I'd have sent her with some dope , tabs or powder in the satchel they'd know PRECISELY what it is , the quality , purity , grade etc ....

I even go to engineering bolt stores knowing precisely what I want and the fools are too lazy to check thru their bolts for the right shank length ...

For Chinese bikes you'd need 2 of the SKF 320/22X's .... then you could get one ground out to 23.5 in a cylindrical grinder by a cluey machinist ... or you could do it by hand with a die grinder or mandrel sander and finish it off with a brake cylinder hone ... You learn to do the impossible by hand when being trained as an industrial tool maker ... Another option is to have your steering shaft machined to take two Jap SKF 320/22X's and be done with it .... Pitsters used to take two 44 x 22 bearings ...