Trials Australia Forums

While we are on the subject of spokes can someone help me with this query.
If I buy a set of correct spokes for a particular wheel that is already spoked up but they are in crap condition, is it possible to replace the spokes one by one and get a good result, by good result I mean running true and with the same off set.
I realise I would have to tension the spokes to the same as the ones I take out one by one and it might need truing up at the end but realistically will it work ? and any special advice I need to take notice of ?.

This is about to happen on my latest project,,,,, about which, my lips are sealed

BTW I got post number 1900 on this topic so that must be worth a carton of bubbly from Greg

I can't imagine that being possible unless the new spokes are the perfect correct length, but even then I can't see you being able to feed the spokes in from the flanges unless you loosen the 'old' spokes right off, and obviously then you'll lose the offset, trueing and tension. (A few older brit bikes had keyhole shaped slotted flanges which allowed insertion of the spokes after connection to the nipples).
Whatever... you need to measure the correct rim offset before you do anything. Some bikes have the rim offset to one side of the hub, you can't always guarantee that they are centrally aligned.

You can do it that way, but if it is a normal drum-brake trials bike type wheel like a Yamaha TY, you would need to bend and re-straighten all 72 new spokes to fit them.

Yes if you do them one at a time and set the tension to be the same as it was with the old spoke, then in theory the rim should be as true as it was before you started. Achieving that is extremely unlikely, so the rim would need to be trued afterwards anyway.

The spokes are a simple repeated pattern.
Take some photos of the complete wheel from a few angles for reference first.
Strip the wheel.
Fit the spokes to both sides of the hub and lay them in the correct pattern.
Lay the rim on them and start feeding them into the rim and loosely fit nipples as you go.
It's not that different to doing bicycle wheels except their spokes are far mor flexible.
Once it's all spoked, mount in the forks and spin.
Slowly tighten the nipples to straighten the rim and adjust the runout.
Just a little bit on each nipple going round and round the wheel.

Be patient

Did that on my Fantic rims, pulled every spoke one at a time but sometimes you have to remove others around it, gave them a good clean and polish with autosol or whatever it's called and refitted with new nipples.Works a treat. Have done the same with Italjet rims fitting new black spokes, just take your time and have some patience.

Hi Everyone,

Roger, I can rebuild your wheel if you like?

smiffy60 wrote:Interesting use and adaptation of the wheels most jennys had half a dozen different wheels that could be swapped over for different uses and you could get a set of wheels that was made to straighten or roll wire for edging sheet metal.

Ray, the wiring wheels (Usually a couple of sizes) are used to prepare the edge of the sheet as a safety edge and to stiffen the opening of a toolbox for example. The only time that wire actually goes through the Jenny is to set down or crimp the sheet onto the wire. A third roller is needed for straightening wire or spokes in this case. Here are a couple of examples, the big box belonged to my Great Grandfather and was used in his travels and the small one is a cheap knockoff that rides in my bike toolbox.



So now for an update: after a while of tinkering and thinking about the problem, I estimate about 9 meters of wire went into making the front wheel. So with that in mind, at some stage the wire had to have been in a coil after going through reducing and straightening rollers. Then cut to length, mushroomed on one end and this is where I think the randomness starts as with short straight pieces there is no orientation to locate which way they get bent for the hub end.

With the straightening process, there has to be residual stress just to keep them straight. Stainless Steel work hardens but was not a problem for me to lengthen the amount that I did, maximum of 7 mm. Obviously it started out soft for them to roll the thread so I was not too bothered about hardness.

Now I am going to speculate that when I compressed the spokes in the rollers, I original curve from the coil revealed itself as the inside of the coil is a tighter radius than the outside and each spoke could come from anywhere in the coil? What do you Think?

My 3rd roller attachment worked and if I did it again, I would move it closer to the main rollers, but it was no magic fix. Just got me much closer to being straight. So I ended up going almost full circle back to the Hammer and Dolly. With the spokes being round, I decided a nylon hammer held in a vice with a hollow concave surface and another nylon hamer with a proud convex surface to hit them with. Using the vice allowed my left hand to position and twist the spokes. Having done this and getting all 36 to a standard that I was happy with makes you pretty good at using a Hammer!


Here is the final result of my mission and yes I have learnt Something!

Thanks for all the responses regarding my spokes, I will get the new set first and see how I go.
Thanks Greg for your offer, will let you know.
Cheers

Well done Greg. As they have always said, Patience is a virtue. So is trying to solve the problem. Good job!

Here's anotherie...
Last week Deano dropped around and shovelled this off his ute.





I just needed another project!!! (KSS / RS might be going onto the backburner for a while).
TY250B. Motor has new piston and is bored, looks to be pretty complete - even has speedo and lights. Yes a *hitload of work... but another great little machine will be saved and used.

Mind you I'll be nagging the knowledgable for info. And maybe a few parts!
First is the rear upper engine mount, pic shows top right one has broken off, I'll fabricate another one and weld it on, but I just want to check that the mounts should be 99mm or 100mm apart. Anyone got a bare frame they could confirm?

Middle pic shows some parts that came 'in the basket' but obviously off another bike. Does anyone know what?
(They'll go Free +postage to a good home if I can get a pos I.D.(

-Jools