I've put about 8,000 miles on rig with a 15mm axle over the past 7 years.
No serious issues , just a minor bend once in a while.
I bought a new 15mm and it too will bend usually with a heavy person in the s/c.
I took the wheel to a local bearing supply house to see about getting a pair of
wheel bearings with an inside diameter of 1 inch and having a new 1 inch axle made up.
No luck. A bearing that size doesn't exist or if it did the bearings would be so thin as to be prone to failure.
The option I'm now considering is finding an 18" wheel with a 1 " hub and using it with a new axle.
I'm wondering what kind of wheel would work.
Any suggestions?
Howard
'74 Moto Guzzi w/ Jawa/Velo 560 sc
Go with a 20mm axle. There is a bearing that you can change out that will work at 20mm. You will need to change the spacer between the bearings. You can even drill out your brake drum to still work with the 20mm axle. The drum brake is fairly easy to hook up to work with your Guzzi by tying the brake cable to the final drive housing and then using the rear brake rod to pull the cable.
I know of no motorcycle type wheels that use a one inch axle. Harley claims to but they are really 25mm.
If you do change to a 20mm axle you could also run a matching Guzzi wheel. That is what we have done on some of the sidecars we have put on my wives two Eldorado's over the years. The one issue of course is fitting it under the narrow fender on your 560.
BTW we also have a set up to modify your stock triple tree's should you want lighter steering.
Jay G
DMC sidecars
www.dmcsidecars.com
866-638-1793
Jay G
DMC sidecars
866-638-1793
Jay,
Do you have the number of the 20mm bearing that will fit?
Haven't had any clearance issues with my 3.50 x 18 tire inside the fender unless of course the axle is bent.
I have a 2nd disk on the front of my Eldo and the stopping is super. No need for hooking up the sidecar brake.
Howard
Howard,
there are definetely several weight classes in between the Jawa and Moto Guzzi that your shaft bent.
My Jawa 350 rig got very badly abused over the years and still the 15mm axle is fine. My fear had been it would break in an eyeblink, that you tell it bent does calm my nerves.
Thank you.
When You make up the new shaft use good Crome Moly steel, like 4140,
Don't go with what a friend calls "Carne de vaca" / "cow's meat" 1020 that has only a fourth of the resistance.
With the bearing I do not remember the number, but thickness and outer diameter of the 20mm bearing are identical with the actual 15mm bearing. I looked that up before I made the first mountain expeditions, 8 years of abuse later the axle is still straight.
I may confirm that the Tchecks used way better materials then Eastgerman MZ and I bet Russians in Ural too.
What did always made me wonder was the inconsistency of the bolts hexagons. The norm calls for 13,17,19,22,24...mm I found 14,8mm, 17,8mm, 25,6mm on my rig.
Good luck
Sven
Sven,
I'm going to proceed cautiously. The first step is to find the right bearings, then I can proceed with getting a 20mm axle made.
Thanks for the info about 4140 chrome moly.
Howard
Not sure the sure on the bearing number as we seldom do these any longer, It has been perhaps 15 years since the last one as I try not to work with Velorex sidecars as they are just to light duty for most modern bikes. If the O.D. of the current bearing is 32mm then you are looking for a 6804 bearings.
Jay G
DMC sidecars
www.dmcsidecars.com
866-638-1793
Hello Jay,
the second number seems to be wrong. 6 series yes, 04=20mm yes. Load rating (second number) would be normally 0, 2 or 3.
My bet is 0=> 6004
I am too lazy to pull out the shaft for measuring.(have my velorex in the furthest back spot in my shop)
Joe,
what dimentions do you have? Then we can look into any bearing data book for to confirm in a finger snip.
By the way a HD axle of 1" as Jay states would be actually 1"-0,016"=0,984"=25mm with maching tolerance plus 0 / minus 0,02mm (+0/-0,0008" )
I presented that to the Velorex break and wheel. That 25mm would NOT fit, while 20mm does fit into the original wheel assembly.
Sven
I machined my own 20mm axle and had to machine the backing plate to match. I did not have any trouble getting a bearing for it, but I don't remember where.
I put 36 thousand miles on the rig before I sold it. My friends tell me it is still going strong and I sold it 5 years ago.
That's great to hear.
Thanks,
Howard
There's some 20mm 4140 HT on the internet. If I get it there won't be a shoulder on the swing arm end unless one was welded on.
Then it was suggested to pin it with set screws. Maybe this is sufficient or a bit cheesy(?).
An alternative is to get 1 1/4" 4140 and have it turned down to 20mm with a shoulder left on one end. Then thread it and heat treat it.
Not sure if the second approach is overkill and a waste of money.
Howard
A set screw setup would be equivilent to a suicide attempt.
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
On most materials I there is a kind of scale (surface with different mechanical characters) so it is old mechanic's good school to lathe down at least 2mm on diameter from the raw material.
Here locally we have on one supplier from Sweden who gives us excellent 4140 30 H Rockwell C all way through, - My main client imports some Brasilian and Chineese scrap 4140, = out side un machinable bone inside soft clay.
When I was still in machining business I prefered to pay double on material for the Swedish steel and have only a third in machining and quarter in tooling cost, most of al: first cut was right ON SPOT.
Do yourself a favour and get it machined by a trustable shop that uses good quality prime materials.
Sven
"so it is old mechanic's good school to lathe down at least 2mm on diameter from the raw material"
Peter,
I'm not sure what you mean. If I want the axle to be 20mm in diameter, what size rod should I start with?
Howard
In the USA the easiest way to end up with a 20mm shaft is simply to buy a used axle from the rear of most Japanese bikes. You can pick them up on ebay cheap or go to your local bone yard.
Or this being a Velorex, while we are not Velorex dealers and as such I do not know what parts they stock nor do I know their pricing but it would seem to me that you could simply buy the swing arm from a 563 which is 20mm. No idea if they changed the swing arm since your sidecar was made, perhaps Lonnie who handles Velorex will have some input on this.
Jay G
DMC sidecars
www.dmcsidecars.com
Thanks Jay.
Lonnie, are you there?
Howard
Circa 2005, the advent of the Cruiser and Tour models, the Velorex sidecars all had the new swingarm with the 20mm axle.
Earlier models including the 560 all had 15mm axles.
In over 25 years I've only had a couple of requests for replacement 15mm axles.
Lonnie
