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T21 M, Cota 248, 1982

Featured Replies

Just building up a 248 bought as a rolling chassis, motor (head/barrel off) and box of bits.

1st headache.

Can anybody post up photographs of the front brake, from the left and directly from the front. With the front brake assembled to the wheel and the wheel inserted into the forks with speedo drive and spacer on r/h side the brake torque sits about 10mm from the fixing lug on the fork leg.

The torque arm is presently straight or flat. There is no evidence of it being straightened.

However, should the torque arm be shaped in order to lie flat against the fork lug?

There is a steel bush pressed into the brake plate. Is this correct?

2nd Query Really.

One the main frame section, there are 2 ribbed tubes in the vicinity of the swinging arm. They are not grease nipples. What are they exactly?

Many Thanks

If the front wheel is central in the forks and the spacers are correct so the sliders are parallel the torque will need to be cranked. Be aware montesa used at least two types of yokes which differ in spacing between the forkes and require different spacers and the thickness of the boss on the brake plate.

As for your other question the swing arm can have a little hose tail connector on each side which sometimes are connected together with a hose which i think should be filled with oil and on other bikes the hose is teed into the gearbox breather on the rear of the engine. I removed mine and fitted grease nipples.

Edited by jimbo349

  • Author

Hi Jimbo.

Thanks for your response. What a coincidence!

I'm actually in Kings Lynn and will be rejoining Dabbers. Used to ride with them on a TY175 about 15 or so years ago. Are you going to Little Thetford on Sunday?

Looks like I will crank the torque arm to suit.

OK on fitting grease nipples to the s/a.

Yep going Sunday its going to be slippy. Good luck with the bike, Ive got a soft spot ffor old monts.

James

  • 3 weeks later...
  • Author

Hi Jimbo.

I see the next meeting is 18th Nov (next Sun). Could not make last meet, so hoping to get to this one.

Front wheen fitting now sorted. Ended up making new spacers.

Need a bit more help now.

How and where does the chain tensioner fit, and does it need a spring to operate ?

Also, what holds the outer front brake cable in position on the forkleg ? Is there some fitting ?

Pictures would be really useful.

Thanks.

The chain tentioner is attached to ome of the crankcase bolts and yes it has a spring. the front brake is attached to the forkleg with a adjuster similar to whats found on a pushbike. I will get some pics later.

  • 3 weeks later...
  • Author

Next problem is the fit (or not fit) of the handlebars.

Bought a pair of Tomaselli, but are actually dia 22mm and will not tighten up in the clamps.

Are there bars, swaged with larger dia in clamp area?

Will I have to turn up a set of shims to fit these correctly??

A friend just bought a 348 Mont' and it had shims between bars and clamps, seems standard.

The original 348 bars were larger in diameter and stepped down at the grips. There was a thriving market in spacers to allow the fitting of Renthals.

And, believe it or not given modern tweaking, adaptors to set the bars back toward the rider.

Edited by 2stroke4stroke

  • 3 months later...
  • Author

Turned up a set of handlebar shims - Fairly straightforward - Bore tube 7/8", turn down O/D to fit into the clamp halves (bottom clamp half is different size from the top half). Had to turn to fit, as the clamp half is not a true 'half', so the diameter could not be measured. Part off to the required length and you have a 'ring'. Turn up a 7/8" plug to fit into the 'ring' and use a toolmakers clamp to hold in the clamp half. Use a model making saw blade (like a junior hacksaw but finer cut) to 'split' the 'ring'. Had to make 2 sets like this one to fit clamp top half, and one to fit clamp bottom half. And I was reading in another thread about 'overpriced restorations'. I think that you have to consider the amount of work that has been put into a restoration when deciding on its 'worth'. Anyway, another question, , chaintubes. How to these fit to the alloy bracket on the rear wheel spacer. I can see in the parts diagram 4 'buttons', which appear to be held to the alloy bracket by an M6 nut/bolt. How does the tube fit over this button? Is it a push fit to allow the tube to 'float'. Pictures would be useful. How are the tubes fixed at the front end? Thanks

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