Rattling front mudguard Sprint 7

[flecc]

Mass market bikes have suffered poor wheel build for years, and today's China production is no different. Building a wheel with even tensions is a skilled thing learnt over time, and it can be a time consuming process. In a production environment it isn't practical to build to the highest standard, just trueness being aimed for it seems.

As for the skills necessary, just consider this. When we built the world's bicycles, Raleigh were the biggest with production peaking at 100,000 per annum. They lasted for 30 years or more then though.

Now China does it in today's world, current production is 70,000,000, and at one time almost hit 100,000,000. So where can anyone get all those highly skilled wheel builders? There's only one place, the paddy fields!
.

 

[Ian]

There's an short program that's part of Discovery Channels "How it's made" covering bicycles, I'm fairly sure it's Marin Cycles Taiwan factory. The whole process is very labour intensive, frame tubes are hand cut, hand shaped and hand welded. The wheels are laced by hand but trued by a machine that is fascinating to watch, taking a few seconds to do what takes me several hours. The tyres are fitted by hand and the bicycle is assembled by hand, the only automation on the assembly line being the power tools in the workers hands.

 

[flecc]

Yes, that's the problem with bikes, it's so difficult to automate production, I daresay that wheel truing machine is better at it than many production people doing that job, but doubt it does the job to the highest standard. Marin are one of the better makes though, even at the lower end of their price range.

I'd still like to see small wheels used more. If a large proportion of the world's bikes ran on 20", we could have motor cycle style three or six spoke alloys or composite wheels, and an end to spokes and all their troubles. Many millions of Minis have run on wheels of about that size for nearly 50 years, so it can't be considered too small. Just means larger chainwheels and ceramic coating of brake surfaces.
.

 

[HarryB]

On the subject of wheel trueness - does anybody know what size of tool you need to adjust the spokes? I bought a multi-sized tool but none of the slots fit the spokes and I am worried about rounding them off.

 

[ITSPETEINIT]

Spoke key size

On the subject of wheel trueness - does anybody know what size of tool you need to adjust the spokes? I bought a multi-sized tool but none of the slots fit the spokes and I am worried about rounding them off.

Hello Harry:
I bought a spoke key (wrench). A round one with the key-holes cut into the turned-over edge (shapes rather like a Jam Pot lid).
There are 8 slots numbered 10 to 15. For some reason there are 2 x No. 14 and 2 x No. 15. The one that fits the Torq spokes snuggly (no fear of rounding the nipple) is No. 13.
It is quite a good fit and a little difficult to get on the nipple, partly because the nipple is very..... there is no taper lead at the spoke end.
Dreamcycles.co.uk UK Mail Order bike accessory, mountain bike part, mountain Ice Toolx Spoke Wrench £3-50.
Hope this helps.
Peter

 

[ITSPETEINIT]

Rear Mudguard Rattle

I've managed to escape brake judder on my Sprint 7 (touch wood!) but do have the rattling mudguard problem. I agree with Peter in that the problems seems to be due to the length of unsupported guard. It is certainly the case on the rear mudguard. I will look to jerry-rig something between the guard and the carrier and see if that helps. The front guard chatters incessantly. Isn't it amazing how irritating these small things are?

I saw a post somewhere that said it helped if the stay(s) are zip-tied to the carrier, where they cross.
It worked for my Torq.
Peter

 

[Tim]

Now China does it in today's world, current production is 70,000,000, and at one time almost hit 100,000,000. So where can anyone get all those highly skilled wheel builders? There's only one place, the paddy fields!
.

Here's a wheel builder at the eZee factory. He's been with the firm for years, since it opened as far as I know, and I found him quietly focussed on preparing and truing wheels whenever I took a random walk around the factory.

 

[Ian]

Here's a wheel builder at the eZee factory. He's been with the firm for years, since it opened as far as I know, and I found him quietly focussed on preparing and truing wheels whenever I took a random walk around the factory.

It's nice to see a face in what to most of us is a very remote and faceless industry half a world away. (The manufacturers, not the local distributors that is). Ezee though is probably more open than most with the owner, Mr Ching being a fairly public figure. Mind you some of the lesser manufacturers would't want to put a face, or their own name to the junk they turn out.

 

[flecc]

Yes I remember the photo of this chap from your 50cycles blog Tim, there will always be exceptions. But it's a long eventful way from China to one of us, and newly built wheels don't necessarily settle well. Even in the days of English production by apprenticed lifelong workers, further attention was often needed by dealers after receiving bikes. It's an inevitability with thin rimmed large diameter spoked wheels.

Those immediately prior to my two eZee bikes, a Giant, a Marin and a Ridgeback all needed correction to the wheels, all with large variations in spoke tensions which meant they would lose trueness with use.
.

 

[ITSPETEINIT]

Wheel Building at eZee in china

Here's a wheel builder at the eZee factory. He's been with the firm for years, since it opened as far as I know, and I found him quietly focussed on preparing and truing wheels whenever I took a random walk around the factory.

Is he the "gentleman" who built the front wheel in my new Sprint 7, do you suppose?
I'd like a word with him!
Peter

 

[redalpha3]

I saw a post somewhere that said it helped if the stay(s) are zip-tied to the carrier, where they cross.
It worked for my Torq.
Peter

Not an option in my case, Peter, as my rear mounted dog basket is fastened at that point also. I see the reasoning behind this though, and will try a workaround. Thanks

 

[Ian]

Shimano Deore XT V-Brake on Torq

Just fitted a new parallel action Shimano XT brake on the front of my Torq in an attempt to stop the judder, guess what, after a 5 mile test it still judders . however it's not as bad as it was, and if it doesn't get worse I'll be happy with it. On a positive note the brake is very powerful , I did have to make some spacers to extend the pivots on the fork by 10mm though.

 

[nigel]

Nigel

Maybe
a disc brake would have been the answer on the torq but not sure if it can be done because of the motor i hope more electric bikes come out with disc brakes even if it means extra weight

 

[flecc]

guess what, after a 5 mile test it still judders . however it's not as bad as it was, and if it doesn't get worse I'll be happy with it. On a positive note the brake is very powerful , I did have to make some spacers to extend the pivots on the fork by 10mm though.

The more I see and hear of this on the Torq, the more I'm convinced the motorised front wheel is at the root.

Shimano often awkwardly use different brake posts on their V brakes, but I think they can be machined down. It's something I'll be trying on my Torq as part of a series of changes to it.
.

 

[Ian]

The more I see and hear of this on the Torq, the more I'm convinced the motorised front wheel is at the root.

Shimano often awkwardly use different brake posts on their V brakes, but I think they can be machined down.
.

The diameter of the posts on the forks is correct for the Deore XT, just as well as they appear to be welded on, but the length is 10mm too short, I made a pair of 8mm OD, 6mm bore, 10mm long extensions which work just fine.

 

[flecc]

Your's is different from mine then Ian, mine's an earlier dynamo model. The posts do unscrew on mine, but seem to have been loctited into place so are extremely difficult to budge. I haven't come across an online supplier who lists the Shimano posts yet, or any posts for that matter, they seem to be a Cinderella in the spares field.
.

 

[Ian]

Flecc, on closer examination it seems my posts may be screwed into bosses welded to the forks, mine probably has the same forks as yours as there is an unused dynamo mount welded on the left.

The Spare parts lists on the Shimano site do show the posts for reference but they have no part number, and I too have not seen any listed by suppliers.

To someone who has use of a lathe (Thats both of us ), the only difficulty in making new posts would be the external thread which, if it's the same as the unused rear posts, is an unusual very course thread.

 

[ITSPETEINIT]

Rattling Front Mudguard and Brake Judder

To all those bicyle engineering theorists:

I recall, from the days that I had a bespoke frame made (and beautiful it was too: none of these aggravations) that the question arose as to the frame angles (Head Tube and Seat Tube) and the Castor Angle of the front forks.
I remember that the head angle could be varied (by a degree or two) to affect the responsiveness of the bike. Thus a steeper head angle would make the front end more responsive (twitchy).
The castor angle is important I understand in generating a force that returns the steering to "straight ahead". The more the centre of the front wheel is forward of the line through the head tube the more 'relaxed' is the steering (that's comfortable for the rider as in Touring Bike as opposed to Racing Bike) and the stronger the castor effect.
The designer/maker of my Touring bike frame (Chas. Roberts) was careful to point out that he would be working within fine tolerances for mine because being a big frame (26 1/2 inches) a good castor angle and a relaxed head angle would put the front wheel 'somewhere out there' (pointing with his hand at an imaginary object about 10 feet away ).
Motor cars have steering geometry in which camber angle and toe in (of one front wheel in relation to the other) also have an effect on steering but this is not relevant to 'vehicles' steered by a single wheel. The castor angle is important in this context too.
I have a feeling that a Supermarket Trolley has something of a 'steering problem' (most of us have experienced this on cambered paths) that comes from this geometry: the front wheels 'trail' behind their fixing point and there's is no castor effect at all (it's probably negative).

Might I be right in thinking that there is something in the design (set-up) of the Torq and Sprint (and maybe the other eZee models) where this factor is responsible for our perceived troubles? There is not much 'rake' on any of the eZee models front forks.
I have no experience of models other than Chopper, Torq and Sprint. The chopper did not suffer from rattling because the mudguard was very much shorter and no less strongly built.
I get this m.g. rattling on the Torq despite the fact that I have fitted full mudguards with two stays on each side.

Peter

 

[flecc]

To someone who has use of a lathe (Thats both of us ), the only difficulty in making new posts would be the external thread which, if it's the same as the unused rear posts, is an unusual very course thread.

I've got a Shimano Deore MX580 V brake that will fit completely onto the existing Tektro posts if the post section with the spanner flats is turned down to the main shaft diameter, and I intend to do that and see what that's like.

That's some way off though, since I'm engaged in many other things on the Torq at the moment.
.

 

[flecc]

I get this m.g. rattling on the Torq despite the fact that I have fitted full mudguards with two stays on each side.

Peter

My replacement plastic mudguard using the original "stubby" mudguard two stay triangulated mounts and straps doesn't rattle at all, probably due to it having a slightly deeper profile than the original, so torsionally stiffer. I found it in Halfords sell-off bin, just luck.
.