Author Topic: My TM250 Project  (Read 7608 times)

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Offline Jumbo J

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My TM250 Project
« on: July 13, 2014, 10:21:24 am »


 

Picked up this original TM250M on ebay about 18months ago from Detroit. Arranged trucking it to New Jersey (uship) and then shipping it to Sydney myself, Customs clearance Quarantine etc. Good learning experience. Plan is to prepare it for the track over time, starting with rebuilding the suspension and replacing all the worn out or perished bits after 40 years of sitting around. Looks to me like the engine has never been split and except for missing the front race plate, nothing has been removed or replaced on the bike since it was new. Will probably save the original (made in japan) cosmetics like tank, guards, side plates etc. and replace them with aftermarket or good 2nd hand gear to protect their remarkable condition for age.

It is a 75 model so i will ultimately source an unmolested straight 74 frame and swing arm to transfer the running gear across to. Haven't got a race licence or joined a club yet, but will be doing that when it gets closer to the point i would like it to be before hitting the track.

Will post more pic's here as i progress through the rebuild journey   
« Last Edit: July 13, 2014, 10:32:15 am by Jumbo J »

Offline DJRacing

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Re: My TM250 Project
« Reply #1 on: July 13, 2014, 10:26:00 am »
Certainly a good score, good luck with the project.
If at first you dont succeed, give up and drink beer

Offline Ktm181

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Re: My TM250 Project
« Reply #2 on: July 13, 2014, 11:15:10 am »


very nice tidy old girl too by the looks of it, one of my all time favourite dirt bikes (TM & RM), AND you did the effort yourself, well done!  Make it reliable and RIDE the sucker!

Kt.

Offline Jumbo J

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Re: My TM250 Project
« Reply #3 on: August 17, 2014, 05:09:01 pm »
Fitted today new cush drive rubbers, brake shoes, fr and r sprokets








new swing arm bushes



oldfart

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Re: My TM250 Project
« Reply #4 on: August 17, 2014, 05:21:59 pm »
Put a shim between circlip  & drive hub to take side play out of the equation . It's also a good idea to replace sprocket mount bolts as they have a tendency to shear off as have been down this path  ::)
Put a grease nipple in your swing arm and those bronze bushes will last for ever ;)

It's looking good .

Offline Jumbo J

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Re: My TM250 Project
« Reply #5 on: August 17, 2014, 06:23:20 pm »
Thanks OF.i shimmed the cush drive rubbers there was a lot of b and fwd play there despite them being new. Now it's solid as. Yes there is some slop between hub and circlip   but I haven't yet worked put what to shim it with. And already done the grease nipple and machined galleries in the pivot shims and bronze bushes. 

What would be a good choice of tyres. They are original and shot.

oldfart

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Re: My TM250 Project
« Reply #6 on: August 17, 2014, 06:50:50 pm »
I made my shim out of a M & F reducing ( steel ) bush turned down in me lathe. ;D
Lasted 3 seasons so far without any play.
I'm presently running  Metzeler  MC 5 ( intermediate) and they seem to wearing  well.

Offline Jumbo J

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Re: My TM250 Project
« Reply #7 on: August 17, 2014, 08:12:35 pm »
I made my shim out of a M & F reducing ( steel ) bush turned down in me lathe. ;D
Lasted 3 seasons so far without any play.
I'm presently running  Metzeler  MC 5 ( intermediate) and they seem to wearing  well.



just checked the clearance gap, its barely 12 thou probably closer to 10, thats a bloody thin shim to spin up. doubt if my guy is set up for precision like that.
thx for the tip on the MC5's will chase down a set.

Offline oldyzman

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Re: My TM250 Project
« Reply #8 on: August 17, 2014, 09:20:29 pm »
Mate, can't you just pack some thing under the cush drives before you put them in the hub, when i fitted a 520 chain and sprockets to my TM, i had a similar problem.
I have a soft spot japanese mxers with aluminium tanks. Two stroke classic Dirt Track...

Offline Jumbo J

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Re: My TM250 Project
« Reply #9 on: January 05, 2015, 09:10:00 am »
Well its been a while with other things distracting me, but here is the current state of the TM. But alas no spark, so after checking coil / plug lead/ cap. etc bought a NOS CDI unit to see if that cures it. Not sure how to check the CDI - any suggestions?


Offline shelpi

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Re: My TM250 Project
« Reply #10 on: January 05, 2015, 10:31:28 am »
get a good manual, it will have all the resistance values and stuff for each component, not to mention all the other specifications for servicable tolerances, good work mate, itsa pearla  ;)

oldfart

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Re: My TM250 Project
« Reply #11 on: January 05, 2015, 01:26:59 pm »
You will need a 50 tooth on the rear as the stock STD  are good for  Land Sped records  ;D

Offline bazza

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Re: My TM250 Project
« Reply #12 on: January 05, 2015, 01:58:50 pm »
Looks good Stew, Happy new year
Once you go black  you will never go back - allblacks
Maico - B44 -1976 CR250- 66 Mustang YZF450,RM250
Embrace patina

Offline Jumbo J

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Re: My TM250 Project
« Reply #13 on: January 05, 2015, 03:58:38 pm »
You will need a 50 tooth on the rear as the stock STD  are good for  Land Sped records  ;D

Could only find a 42 / 520 rear Stew. (DR370)  with a 12T on the front. would prefer a larger rear if i could find one to fit the hub

oldfart

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Re: My TM250 Project
« Reply #14 on: January 05, 2015, 04:48:49 pm »
Give Titmans a call  they should have mine stored in a computer
Aluminium blank drilled to suit.... end result  ;D