Radwagon rear spoke tension adjustment

Peter R.

New Member
I have about 300 miles on my Radwagon and I have been having trouble with loose spokes on the rear wheel. I weigh about 200 pounds and my wife is about 110 pounds. Well within the 350 pound limit but driving around with her on the back has caused the spokes to loosen considerably.

I tightened all of the spokes 1/4 turn and the rattle of the loose spokes went away. The wheel remained true. I don't think they are tight enough to resist loosening when I put extra weight on the bike. Radpower technical support suggested I tighten another 1/4 turn but I am holding off until I get a spoke tension gauge and can balance the spoke tensions on the wheel. I can't hear the difference in pluck tone in these short 12 gauge spokes so I can't use my sound method I use for longer, thinner spokes.

Anyone got any advice on wheel balancing with short, 1 cross 12 gauge spokes?
 
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flymeaway

Well-Known Member
Anyone got any advice on wheel balancing with short, 1 cross 12 gauge spokes?
Get the TM-1 Park Tension Gauge, use the provided chart to tension the spokes according to the wheel manufacturer's specification. If the vendor that sold you the bike can't provide the tension spec. for the wheel I'd say you have a problem. Plucking the spoke and "comparing the sound" with other spokes to get uniform tension ?????? within a range is OK to get you out of trouble, but improper tension on the spokes is asking for trouble.

Court J.
 

Peter R.

New Member
Get the TM-1 Park Tension Gauge, use the provided chart to tension the spokes according to the wheel manufacturer's specification. If the vendor that sold you the bike can't provide the tension spec. for the wheel I'd say you have a problem. Plucking the spoke and "comparing the sound" with other spokes to get uniform tension ?????? within a range is OK to get you out of trouble, but improper tension on the spokes is asking for trouble.

Court J.
I should get my TM-1 in a few days and I plan to measure the tensions on all the spokes and then increase and balance the spoke tensions to the highest spoke tension plus a bit. All this while keeping the wheel true. Radpower tech support said to set the tension for 12 gauge Stainless Steel spokes. I have not been able to find this online. No mention of the rim's tension spec.. No name on the rim either. Not much help at all really but fast reply and very polite. I will ask them for the maker and model of the rim.
Update --- Radpower tech support has supplied the rim make and model for the Radwagon but there is no info on the makers site re spoke tension ranges for the rim. Alex Rims (DM24) These rims are not mentioned in the Park tools list of wheels and tension recommendations. So it goes.
 
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Ann M.

Moderator
Peter, once you get the tension meter and know what the correct tension should be (don't over tighten) make sure the wheel is true and add 1 drop of purple thread lock to each nipple to help prevent the spokes from loosening. Don't use anything stronger because the time will come when you will need to do truing after hitting a few potholes with a full load on back, but this will help reduce loose spokes. Pedaling while starting from a stop will help a bit too, since hub motors produce a lot of flex and stress when first starting.
 

TenBlinkers

Member
I've had trouble with loose spokes on my RadWagon as well. Had to have them tightened twice in the first 1,000 miles, and the rear wheel re-trued once. I had the bright idea of getting a spoke wrench to prevent some trips to the shop, but I snapped a spoke. I'm now the proud owner of a box of 12g spokes, and have the number of one of only two shops within 100 miles that can cut and thread 12g spokes.

Tension gauge sounds like it might be a good investment, but I worry that I'll knock the wheel out of true if I start messing with that.
 

Ann M.

Moderator
Usually, @TenBlinkers folks invest in a Truing Stand as well as a spoke tensioner to do a really good job on a wheel. You're right, if you just blindly start tensioning spokes the wheel may not necessarily be true. For just one or two loose spokes a rough approximation of truing can be done by lifting a rear wheel off the ground while still mounted on the bike (there are some double kickstands or bottom bracket bike holders that will help you do this) and use the V-brake pads as an alignment if you have those. Otherwise, a pencil, zip tie or other small straight object can be used for reference. If you're using a truing stand, you really are supposed to remove the tire and tube to do the work right. If it's the rear wheel with gears, you'll also need to watch the centering of the rim with respect to the cassette or freewheel, this is dishing. Spokes on the left and right side of the wheel are different lengths in the rear.

Bottom bracket bike stand by Sunlite.jpg
Bottom Bracket bike stand
Truing Stand by Sunlite.jpg
Simple Truing Stand by Sunlite

Here's a decent video on basic wheel truing (BTW, when the tech says 'spoke key' think spoke wrench :))


Or for a really thorough written explanation about wheel truing, read Sheldon Brown's online guide.
 

Peter R.

New Member
Anne, thank you for the information. I have a copy of "The Bicycle Wheel - Third edition" by Jobst Brandt which is pretty good. I have been using a pair of cut off plastic ties on both sides of the frame to make sure nothing moved while I was snugging up the loose spokes. I may get a truing stand eventually but I will try adjusting it on the bike first. The Radwagon has a full kick-stand built in (you can rig it to keep either the front or rear wheel off the ground while you work on it) but I prefer to hang the bike on a repair stand so I can sit down and work at eye level. Great fun learning about all this.
 
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Ann M.

Moderator
I like that book too for reference, Peter. Although Park stands are the best, they can be pricey. The Sunlite stand in the pic above is pretty inexpensive, around $50. And yes, done the plastic tie thing too :)!
 

TenBlinkers

Member
I might end up taking it to the LBS when necessary - not sure how DIY I want to get with this . Plus, my garage is full! :)
 

SnowyMonk

New Member
Just wanted to add that I got an e-mail from RadWagon saying that tension should be 80-85 Kfg. And use the park tools SW-3. Also... I know the specs says 12 gauge spokes, but the tool that came with the tensionometer has my spokes measuring 2.16 mm... which is somewhere between 13 and 14 gauge right? Anyway.... figured I'd add this info as this page has been helpful for my tru-ing needs.
 

Jonchui

New Member
Hey all

Just got my radwagon yesterday and after riding 15 miles with my two boys (55 and 40 lbs) In the caboose am noticing the rear spikes making a weird noise.

https://photos.app.goo.gl/HV491KVox8n3VMbH7

I don’t have a Tork wrench but touching some of the rear spikes they do seem more loose than others.

Also the grey line on the rubber side of the wheel does not stay consistent when the wheel turns (so though it may be true for the bike rim, I think the rubber may not be true)

Can I Just use a normal wrench to tighten the loose spokes?
 

Mike's E-Bikes

Well-Known Member
I might end up taking it to the LBS when necessary - not sure how DIY I want to get with this . Plus, my garage is full! :)
Excellent idea. If you don't know what you are doing, you can really mess things up. Tensioning without truing properly can make it worse. This is not something an average DIY person should probably do, and it requires a lot of practice. I'd suggest practicing on several regular bike wheels before attempting on ebike rim with motor. It's a very slow process and if you are not a generally patient person, willing to be methodical, then Def take it to a local bike shop who has a wheel builder with good reputation for truing and tensioning.
 

TenBlinkers

Member
Agreed. The first time I tried tightening my own spokes, I broke one. I still do a little tightening now and then, but its part of my spring tune-up to have the LBS true the wheels.
 

Mike's E-Bikes

Well-Known Member
If it were me, carrying that much weight, I'd consider having the wheel re-spoked by a professional wheel builder and also have them check that the rim is of correct thickness for 12 GA spokes. If not, could be a good idea to also replace the rim. The wheels are likely machine built, and so if they aren't properly pre loaded then retensioned again after riding some decent level of miles, you can keep expecting the spokes to frequently get loose again and again, especially if the rims were a bit on the thin side to begin with. It's not easy to build and sell a quality ebike at this price point to begin with, so certain areas like spokes and rims , especially on the hub motor wheel, are worth the extra money to invest in. Probably more so than people upgrading controllers or their display, or motor output, which seems to be a common topic among owners of these ebikes like Rad and Sondors.
 

Jonchui

New Member
Okay guys thanks for all the tips and advice. Love how fast you replied. Love communities like this!!

Well I did another 10 mile commute and the noise is louder than ever so I bit the bullet and took it into a shop to have it retentsioned.

Only problem is the TM1 he had didn’t fit between the hub flange and the spoke crossing. So he just used a normal tool to tighten everything.

I’m wondering how you guys fit the TM1 in?

Now I’m wondering if I should buy a fork wrench to do it myself ?

I’m just wondering if having my two boys (90lbs) in the caboose is part of the problem?
 

Attachments

TenBlinkers

Member
Mine fit (wasn't the TM1), not sure what the LBS uses. My guess is that the boys on the back just shortened the time when you'd need to tighten the spokes. Its a known issue on the wagons - the spokes just get loose periodically.