4 spokes broke in the space of one week

[Magzy]

6 spokes have broken in the space of a month (4 in the last week) and used up all my spares.
They all broke on the curvy notch section that touches the MP wheel...

The cause was either down to:

1. The unusually cold weather here in AUS (shortening the spokes that were already tightened in the heat)
2. having just fitted a infineon lyen edition 9 fet controller pumping out 32A peak @~48v)
3. my portly 100kg round figure being too heavy for bike (my wife thinks is the cause but she's not technically minded)
4. hitting bumps too fast (with my hard tailed mtb)
5. A combination of all four...

In any case, I'm out of spokes and I fear that I'll be popping them out like the clappers without any backup spokes to replace them.

Where can I get a good, fast, reliable, cheap source of spokes for a MP on a 26" wheel?

I mailed Golden motor China (with a simple email) about 3 weeks ago but I got no response (...and this does not surprise me)

[Bikemad]

I would try Gary at goldenmotor.ca, as he normally keeps these in stock.

Alan
 

[Magzy]

Thanks Bikemad - he has a page:
http://www.goldenmotor.ca/shopping/pgm-more_information.php?customernumber=&id=81

Incidentally, the guy who sits next to me at work says that a rubber washer where the spoke contacts the hub may reduce friction... It's the heat buildup at the weak point that just causes it to snap off.


Same thing happened this week on his road bike and the guy in the bike shop told him it would prevent snapping spokes...

[GM Canada]

Hi Magzy

I find it odd that very few people break spokes, but those that do break spoke after spoke after spoke. I did have a wheel that was doing this to me on a regular basis thi spring. Since I had done a few wheel builds with success I decided to loosen all the spokes on the wheel that was breaking them. I re-tightened all the spokes truing the wheel better then it was before even. Now I have not broken a spoke in months. I think some wheels have the spokes to tight. There is a delicate balance between to tight and to loose that is imposible to describe.

Gary

[Magzy]

Hey thanks Gary.

Yeah, I remember tightening them really tight because a couple of them were coming lose after a couple of k's and maybe the extra strain of (1592 W   is too much to bear for them...

Maybe a blob of super glue on a "reasonably-not-so-tight-but-tight-enough" set of spokes will do the trick.

Thanks for the tip.

[Cornelius]

Sound are a good way to tell if a spoke have the right tension. (Plonking a spoke creates a specific tone at a specific tension.)

If for example Gary could agree with himself when each specific wheel are true and have the right tensions, he could publish the note for each size. There would be a different note/tone for each size, and for pie/prokit...

Ofcourse, not all spokes can be set to exactly the same tone, since trueing would mean slightly different tensions of the individual spokes, but having a base note would be a good start.

Searching the net for 'spoke tension by tone' gives a good deal of info...

[DirtyGinge]

Spokes, like all metal, fatigue over time....for instance sapim strong spokes are rated at 1.6 million revolutions, where as sapim leader spokes are rated at 800,000 revolutions.....basically your wheel sounds metal fatigued......change all the spokes out now......

Go to somehwere like a BMX shop, who may create "racing" or "jumping" spokes of a specific length for you...

May also be worth considering changing the rim also, as this will follow shortly

Here was my rebuild on MTB downhill extreme kit

http://goldenmotor.com/SMF/index.php?topic=3187.0

[Magzy]

6 more have broken now - even after losening them

That's 12 broken spokes in 2 weeks 

Anyone any idea what's going on?

The bike is now unusable.

Now I need to get a new full set of spokes for the MP standard 26" rim   

[SydneyCommuter]

Question

What do you guys do for spoke tensioner, I tried the usual bicycle ones and they are too small for those solid PI spoke tensioners (if that is what you call them) do you have to go for a motorcycle one??
I'm about to rebuild so it would be helpful.
tks
Mark

[MonkeyMagic]

spoke wrenches these fit everything I've had, but I am no spoke guru

[Magzy]

I have found a custom spoke maker here is syd who can make 10 for considerably less $'s than buying a full set from canada ans shipping them for $20 on top of that (quite frankly I can't afford it)

I need to know what length of spoke the MP is on a standard Rim (that comes with the pie)
Along with the spoke hole diameter. (i.e. what gauge)




plus anything else I need to give the spoke guy in the shop.

[Bikemad]

If you take your wheel in with you, he can measure the exact size spoke that is required.

He should also be able to see if the elbow of the spoke fits correctly into the hub, and may be able to advise on whether washers are required under the heads of the spokes to remove excessive lateral movement in the hub fixing holes. 



Alan
 

[GM Canada]

Question

What do you guys do for spoke tensioner, I tried the usual bicycle ones and they are too small for those solid PI spoke tensioners (if that is what you call them) do you have to go for a motorcycle one??
I'm about to rebuild so it would be helpful.
tks
Mark

I Use this from Canadian tire..



Costs a whooping 3.99 and works great.

Gary

[Magzy]

I just need the effective MM length and the MM Diameter (gauge)

The rim is a Standard 26" MP supplied rim so the ERD is the standard.

[GM Canada]

I just need the effective MM length and the MM Diameter (gauge)

The rim is a Standard 26" MP supplied rim so the ERD is the standard.

I get 110 mm from the tip of the spoke to the inside of the bend in the elbow. I know somewhere on the forum I measured the thickness but I can't recall where.

Gary