My pitbike is better than yours :)

[gnomester]

Well it is not meant to be a pit bike but the 10" wheel has proven to be useful in trying to bolt up some 1997/98 RM125 forks into a 1996 TS125



It is a very close fit, but the fork stem from the RM125 will need to be machined to the same height as the TS125 and the thread for the stem nut will need to be cut into the stem to the same depth as the TS125.

Can anyone tell me how to press the fork stem out of the clamp so that i may pass it onto my friendly machine shop to do the necessary work to make it fit my bike?

thanks   

[DR]

Gnomester, I admire you for showing some lateral thinking but trust me when I say from experience, the setup you are trying to install is a lot of work and unless you plan to shorten the fork tubes or use a shorter pair of forks then it's going to ride like a pig. No offence but there is no way (well there is a way but it comes back to $$$$ much trial and lots of error) to get the rear suspension somewhere in the same ballpark as the front will require it to have about 7 to 9 inches of travel. It is possible but 2 stumbling blocks are the swingarm is too short and the swingarm pivot is too far from the front sprocket which means the chain will drag heavilly over the top of the swingarm eventually carving it's way to oblivion. The geometry will be all over the show as well which can become dangerous when the bike plows straight in corners or gets the dreaded headshakes at speed. If I was building this bike I'd personally be selling the '77/78 front end complete with clamps and hunt up a pair of TM250 clamps. These are 35mm and you will have a few more options as to what forks can be used to increase travel slighty but still retain rideability. Sorry to be so negative but the chassis on the TS125 without major reworking will never allow it to be an RM wannabe.     

[gnomester]

Thank you for your honest reply DR .... I will heed your advice and look to retaining the standard forks while I try to hunt down some  TM250 clamps and a less aggressive alternative front end.
I was aware that I would have needed to do some work to the swingarm to try and restore the steering head angle to within an acceptable degree but I didn't even think of the problems associated with the front sprocket and swingarm pivot.

The forks were a tip find about ten years ago so there is, so far, no loss in attempting to fit them up and it is good to know what does and doesn't fit.
I also have a front end from a 1982 RM80 which has the same diameter fork stem as the TS125 but is shorter in length so it too will not bolt up into the TS steering head. But the 33mm RM80 forks have a bit more travel and are much lighter than the 30mm TS125 forks.
Maybe a 1980 RM80 drum brake front end would be another viable option 

Time to get the vernier out and do some measurements 

[DR]

okay,with the 33mm fork the easiest clamps to fit these would from a TS185er from around '80/'81. These clamps are offset to suit the leading axle forks. If you use the older style clamps with leading axle this too will affect handling quite dramatically. I have another TS/TM frame arriving at easter hopefully, when I get it I'll sit down and see what clamps/steering stems I have that fit that could save you a bit of time. I know TM250 for sure but not 100% whether you need to use the TM125 steering stem or the 250 stem as the model you have is based loosely on the '75 RM125. The stem on the '75 RM125 is the same as the 250 where all the earlier models all use the TM125 length.

I watched a complete set of clamps sell on ebay US for $12US during the week and the postage was $38us which in total ($50US) isn't bad price for parts that are hard to find down here. As for the RM80 forks, the 82ish models all used 30mm but they are of leading axle type and finding suitable clamps maybe be an issue due to 80 clamps being narrower.

 Maybe keep the RM125 clamps, shorten the stem and fit them as you were going to but instead of using the RM fork legs maybe hunt up a pair of DR500 legs which are the same 36mm diameter as the RM125 but a little shorter. I rarely settle on Plan A with my projects, normally it's more like about Plan L until I find a combination I'm happy with.

[jimson]

I think Pokey fitted early RM80 fork tubes to a TS185 pm the bloke he might fill you in and save a head ache or two.jimson

[pokey]

74 TS185 lowers and valves
 Rm 80 tubes
TM125 top clamp
TM125 lower clamp and tube.

The TM125 top clamp needs to be used as the RM80 tubes are longer and need to slide up to have the same length. the TM bar clamps are swept back a bit so the tubes will clear the handle bars.

Pretty simple and its all Suzuki

[gnomester]

Thanks for that info pokey .. very handy 
I guess the offset with the TM125 clamps and TS185 lowers keeps the rake and trail within the good numbers.

PS... the 1982 RM80 forks and clamps that I mentioned that I had turn out to be 1986 RM80. They were a good price and it was the seller who told me they were 1982 model.... I should have twigged when I saw the disc brake lower 

[pokey]

The RM forks have air caps but the 185 have three position adjustable  caps  for pretentioning the spring

[DR]

mmmm..just a sec, I think the 86 RM80 are still 30mm fork so swap the lowers from the TS forks and all's good is it not Pokey?.. yes/no have I missed something..let me re-read

[LWC82PE]

RM 80

79-85 - 30mm
86-88 - 33mm

[pokey]

Who'd have thunk someone other than me would be after skinny forks?.. Go figure. Chk out those nice emulators from walter , im seriously considering them as an addition.


 LWC is correct with the sizing, 86 and later are 33mm

My issue was to keep my bike pre 75 legal and light. That meant no forward axle and staying true to the 30mm dia where the later model RM 80 forks have 33 and forward axle .

other forks to look at that are not forward axle are the TF Ag bike forks. could even have decent valving being a later model bike  but will have larger tubes

 the TM125 head stock is the same angle as the TS.
 if you want better handling and not concermed on weight, go the TM250 front end . larger tubes and same length and angle .......i think. or bore the TM125 clamps and fit the 250 tubes , they have the meat;)

Forward axle and changed head stock clamps equal different rake on the forks = different wheelbase length/balance= different handling characteristics.
 TM125 are  the same as all the early small bore TS series as measured by my eye