Centre Stand. Fitting Return Spring. ETZ 250

[nice2day]

I had fun and games yesterday trying to fit that very powerful spring back onto the bike, it had me getting annoyed and cursing. I guess it would not have been so difficult if I didn't mind damaging or scratching the new paint. Eventually after much thought, expended energy and failed attempts I created the perfect, easy to make, tool to pop the spring on safely in a matter of seconds. With the tool you can even fit the spring with the bike parked up on the centre stand as there is little to be gained stretch-wise when the bike has the stand in the up position. Before showing the device (it's not that spectacular) I was wondering how others have got on with the fitting the spring and the methods they have used?...Well it's something to write about....

Les

[Puffs]

I'd like to see your tool Les, but honestly, fitting that spring is not something I often do. I probably used a bit of steel wire & a wood leverage arm, but for the life of me I cannot remember.

I had fun in games w/ the sidevalves of the lawnmower, making a tool to get those valves out more easily...

[Kruh]

A decent spring puller does the trick for me.
In some instances I pull it with the puller close to the pin and then with the help of leverage from the screwdriver i slide it on the rest of the way.

But the prefered and safer method is a spring puller.
As for that MZ spring, when the puller didn't work I just made a bigger one. Used a bigger bar so I can pull, or in this case, push it on with both hands with the centre stand down.

[Blurredman]

I usually use tie wraps as an easy handle.. or put coins in the spring slats.

[nice2day]

Sorry for the delay in replying, I have had to complete some urgent work and thanks for all your suggestions.
Anyway as promised here is the NOT very spectacular tool I made up.
Even so, it does work very well but as Puffs says, it's not a job you need to do every day, so maybe this tool would useful for an MZ mechanic
I did consider using a made up puller but the spring is extremely powerful and after testing the stretch, was convinced that if pulling it upwards it would actually lift the bike off the ground but I suppose you could sit on the bike to stop this but I reckon you will need both hands on the puller so not easy to guide the top loop into position.
Pulling downwards is not easy with a puller and using a a wood lever is awkward as you need to guide the loop over the peg.

Anyway, all I did was to squash a thin wall tube in a vice so it just slips over the stand peg and then squeeze the tube a bit more further along so the spring slips easily along it and off onto the peg. Using it is very easy as the tube is located securely on the peg and cannot slip off. With the bike on the centre stand, the tube is fitted on the peg (with the squashed oval profile in the vertical position) about 1cm. You then just lever down effortlessly with the long lever and the spring automatically slides along and onto the peg in one easy motion. You then remove the lever and move the spring back onto the groove of the peg. This is all done safely and without strain. Hopefully someone will find it works well.

Les

[Puffs]

Good idea & I see how it works, ta for the tip Les!

[nice2day]

Thanks Puffs. What I forgot to mention is that the squashed section of pipe also acts as a "limiter" and prevents the spring sliding up the tube and further away from the peg during the initial downward movement of the lever before you reach the main stretching point.

Les

[Puffs]

Yes I see Les.
Just went downstairs to have a look what that spring looks like, and I think I fitted it when upwards, as said with a loop of steel wire around a piece of wood used as an arm, on one side resting on the end of the centrestand. Your method is easier & safer.

[DAVIDGUEST123]

Hooks with handles....bits of twin and earth wire...home made levers .......then I saw the light. Thanks Mr Millyard
https://www.youtube.com/watch?v=e1iLaCHKiRQ

[nice2day]

Hi David thanks for showing this. This trick is quite an old one and I have tried it several times including trying to fit this centre stand spring. The problem is the washers tend to fall out especially when you need lots of them to get the right extended length. I also think you need rough surfaced washers as they would be less likely to skid out. The other problem I find is that getting a couple in to start with is easy but it gets progressively more difficult to get more and more in as the spring becomes so tight and you have to bend the spring more and more which becomes much stiffer and then the earlier ones fall out. You can even damage and permanently distort the spring too as the bend angle has to be get more and more acute. The video shows one set up that only needs a 4x washers (2x each side) that extends the spring by just 3-4mm max but often you need far more extension and consequently it doesn't always go that easily. Thanks again though.

Les

[DAVIDGUEST123]

Sorry it didn't work for you. worked a treat for me with 2p coins as they have a very slight lip. They have to be placed facing each other and fitted from one end... Skinning a rabbit can be done many ways, the right way is the one that works for you

[DAVID THOMPSON]

round of hand clapping for the fellow in the u tube video

Dave

[Puffs]

Well no, I'm with Les on this.
Do as you like, but often springs needs to be extended way to far for fitting washers or coins in-between the windings to be practicable.