Shock absorbers

250 2c- the Wee-WeeVees
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buzby
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Shock absorbers

Post by buzby »

I'm building a 250 twin from an Ebay project and it has some parts missing. Can somebody tell me please how long the shocks are and if you have bought new ,where from ?
thanks,Dave.
David
75 350 Strada, 76 350 Strada, 76 350 Sport. 80 250 vee, 72 Triumph TR5T and 81 Honda CB250RS
ainsty rider
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Re: Shock absorbers

Post by ainsty rider »

just been and measured mine. 300mm between bolt centres. they have the name Sebac on the collets, I think they
are original to the bike slightly leaking after 37 years.
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buzby
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Re: Shock absorbers

Post by buzby »

That's great , thanks very much. I am ordering some new ones from NJB shocks and they have never supplied a set for the 250 vee twin. The Sebacs were, as you thought , the original set.
Dave.
Last edited by buzby on 03 Sep 2019 07:13, edited 1 time in total.
David
75 350 Strada, 76 350 Strada, 76 350 Sport. 80 250 vee, 72 Triumph TR5T and 81 Honda CB250RS
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Ming
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Re: Shock absorbers

Post by Ming »

I have a pair of 320mm (from China) on mine - they were on the 350 until I got some Hagons for that. They seemed OK on the 350, not tried them yet on the 250.
norbert
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Re: Shock absorbers

Post by norbert »

300mm is also the original length for the 350 sport or strada
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buzby
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Re: Shock absorbers

Post by buzby »

Thanks everybody for your replies. Might using longer shocks cause problems with the chain ?
David
75 350 Strada, 76 350 Strada, 76 350 Sport. 80 250 vee, 72 Triumph TR5T and 81 Honda CB250RS
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Ming
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Re: Shock absorbers

Post by Ming »

The shocks that came off (Marzocchi oil-damped ones) were 320mm eye to eye, so I just took that measurement as correct.
MickeyMoto
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Re: Shock absorbers

Post by MickeyMoto »

buzby wrote:Thanks everybody for your replies. Might using longer shocks cause problems with the chain ?
It will put more weight on the front, so the handling may change...
norbert
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Re: Shock absorbers

Post by norbert »

I´ve put 315mm Konis in Dulcinea. The lower trum of the chain tends to touch the frame so I´ve mountet a piece of a special resistant rubber on that little part of the frame tube (still there after 18 000 km). A piece of nylon also can do that job.
There is a little more weight on the front (in my case with about 5 l of gasoline 70 kg on the front and 75kg on the rear wheel). Rocinante has 300 mm shocks and a Fridegotto swing arm, that is 20 mm longer than the 350 serie (it´s in the middle of the 350 and 500 swing arm). Steering on Dulcinea is a bit more lively but fine :wink:
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Ming
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Re: Shock absorbers

Post by Ming »

Just had a look at the road test in 'Which Bike', back in 1980, which says that the rear suspension is by Sebac, so my 320mm Marzocchis were probably not original and should be ignored (though they do fit OK).
mbmm350s
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Re: Shock absorbers

Post by mbmm350s »

Great to see another 250 2C being revived - they are such nice bikes.

Our 2502C has run 300mm (between mounting eye centres) Marzocchi A73 or Euro74 - cant remember which though, since 1993 with no issues.
If you use much longer I think the tyre will be on the ground with bike on centre stand.
These shocks are the same as on the 350 Sport I have.

If you haven't got a parts book - Thanks to our friends in Germany you can download the parts book here:

http://www.hofmann-andi.de/morini/Ricam ... 250_2C.pdf

This is for the first series , there are some changes for the second series that has the plastic rear tail unit

Later we will discuss the best tyres for 250 2C :D

Mark
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buzby
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Re: Shock absorbers

Post by buzby »

Thanks everybody, good progress being made with this project. I did have a another 250 2c many years ago which I bought from Benjy Straw, the number is VWC 850W. I have some pictures from that time and if the present owner is on this forum, I can forward them..
David
75 350 Strada, 76 350 Strada, 76 350 Sport. 80 250 vee, 72 Triumph TR5T and 81 Honda CB250RS
norbert
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Re: Shock absorbers

Post by norbert »

Mark is right acording to the rear wheel touching the ground on the center stand!
I had to weld a piece of steel to the stand using 315 mm shocks (instead of 300) in an early 350 frame.
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Re: Shock absorbers

Post by Hugo »

I have hagons on mine
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buzby
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Re: Shock absorbers

Post by buzby »

The new NJB shocks have arrived. I have Hagons on the other bikes so it will be interesting to compare them.
David
75 350 Strada, 76 350 Strada, 76 350 Sport. 80 250 vee, 72 Triumph TR5T and 81 Honda CB250RS
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