fender/chainguard question

[me]

Is it just me? Am I missing something?

Fenders are designed to keep mud and water off you,
Chainguards are mostly designed to keep grease off
you and in the old days water off the chain.
These days they seem to have mostly given up with
chainguards because of the problems incorporating
the deraillieur movement.

I am thinking of making an attatchment to my rear
fender which will hang down from the front right
hand side to divert water spinning off the downward
side of the rear tire to keep it from washing the
grease off the chain and coating it with crud.

What do you think? Will this be an improvement from
the point of view of chain maintenance? Can you forsee
problems? The tricky bit is finding something will
hold the appropriate shape, if I have to I can fabricate
something from fibreglass.

Comments please, I intend to be riding thru the winter
and it gets v. mucky here.

 

[DougC]

me wrote:
> Is it just me? Am I missing something? ....
I asked about this too a while back (on a couple newsgroups)--if there
was anyone making a chainguard that would fit over a front-derailleur.
Nobody knew of one, though if a bicycle uses a single chainring, they
are common in Europe and I did found a couple US sources. -I am posting
from the center of the US and just about the ONLY bikes you find here
sold with chainguards anymore are those that have no derailleurs--either
single-speed bikes, or multispeed hubs.

A lot of US replies were along the lines of advice to just use a strap
or pant-leg clip (stainless steel) to hold your pants off the
drivetrain--which I was aware of--but these people did not understand
the problem. The point is to prevent oil from EVER getting on you, if
you are riding, carrying, or transporting the bicycle in a vehicle. And
for that, the drivetrain needs to be covered.

> What do you think? Will this be an improvement from
> the point of view of chain maintenance? Can you foresee
> problems? The tricky bit is finding something will
> hold the appropriate shape, if I have to I can fabricate
> something from fibreglass.
>
If you can use a flat piece of "something", then I'd go with the .030"
polycarbonate and zip-ties. Polycarbonate/Lexan is lightweight,
shatterproof, rustproof and inexpensive (don't use acrylic!). If you
need a permanent curve in it, you can form it with a heat gun somewhat,
but it may bubble white a bit.

> Comments please, I intend to be riding thru the winter
> and it gets v. mucky here.

I commend you; my patience with US-Illinois muck is such that I'll be
moving to the desert-southwest US next spring.

[-fini-]

 

[[email protected]]

your lbs can order a universal chainguard from j&b importers
its a two piece design, so has the guard can be made shorter or longer
for the bie you are puttin it on, it fits over d'rails easy

DougC wrote:
> me wrote:
> > Is it just me? Am I missing something? ....
> I asked about this too a while back (on a couple newsgroups)--if there
> was anyone making a chainguard that would fit over a front-derailleur.
> Nobody knew of one, though if a bicycle uses a single chainring, they
> are common in Europe and I did found a couple US sources. -I am posting
> from the center of the US and just about the ONLY bikes you find here
> sold with chainguards anymore are those that have no derailleurs--either
> single-speed bikes, or multispeed hubs.
>
> A lot of US replies were along the lines of advice to just use a strap
> or pant-leg clip (stainless steel) to hold your pants off the
> drivetrain--which I was aware of--but these people did not understand
> the problem. The point is to prevent oil from EVER getting on you, if
> you are riding, carrying, or transporting the bicycle in a vehicle. And
> for that, the drivetrain needs to be covered.
>
> > What do you think? Will this be an improvement from
> > the point of view of chain maintenance? Can you foresee
> > problems? The tricky bit is finding something will
> > hold the appropriate shape, if I have to I can fabricate
> > something from fibreglass.
> >
> If you can use a flat piece of "something", then I'd go with the .030"
> polycarbonate and zip-ties. Polycarbonate/Lexan is lightweight,
> shatterproof, rustproof and inexpensive (don't use acrylic!). If you
> need a permanent curve in it, you can form it with a heat gun somewhat,
> but it may bubble white a bit.
>
> > Comments please, I intend to be riding thru the winter
> > and it gets v. mucky here.
>
> I commend you; my patience with US-Illinois muck is such that I'll be
> moving to the desert-southwest US next spring.
>
> [-fini-]

 

[[email protected]]

me wrote:
>
> I am thinking of making an attatchment to my rear
> fender which will hang down from the front right
> hand side to divert water spinning off the downward
> side of the rear tire to keep it from washing the
> grease off the chain and coating it with crud.
>
> What do you think? Will this be an improvement from
> the point of view of chain maintenance?

I think it might help some, but I'm not sure how much. The question
is, how much muck lands on your chain from that direction? Personally,
I don't think it's much. But YMMV.

I suppose you could put some double sided tape on your chainstay to see
ahead of time how much stuff hits and gets stuck. It might indicate
whether this is worth pursuing.

> Can you forsee problems?

Be sure your chainshield is strong enough, and rigidly mounted. Be
sure it doesn't interfere with removing your rear wheel, or with
re-mounting a dropped chain. And be sure it doesn't interfere with
pants cuffs, or panniers.

> The tricky bit is finding something will
> hold the appropriate shape, if I have to I can fabricate
> something from fibreglass.

Or many other plastics. Or aluminum sheet of appropriate thickness.
Etc.

>
> Comments please, I intend to be riding thru the winter
> and it gets v. mucky here.

Do you have data on your chain life and the your mileage between
re-lubricating? It would be nice to see a before-after comparison,
especially if your chainshield is the only change you make.

- Frank Krygowski

 

[me]

On Mon, 06 Nov 2006 07:58:49 -0800, frkrygow wrote:

>
> me wrote:
>>
>> I am thinking of making an attatchment to my rear
>> fender which will hang down from the front right
>> hand side to divert water spinning off the downward
>> side of the rear tire to keep it from washing the
>> grease off the chain and coating it with crud.
>>
>> What do you think? Will this be an improvement from
>> the point of view of chain maintenance?
>
> I think it might help some, but I'm not sure how much. The question
> is, how much muck lands on your chain from that direction? Personally,
> I don't think it's much. But YMMV.
>

I can't see where else the majority of crud would be coming from. The
spray from the contact patch is gonna go mostly behind, whereas there
will be a fairly constant stream flying off from the sides of the tire
on the downward / forward section of the tire. Maybe I'm wrong.

>
>> Can you forsee problems?
>
> Be sure your chainshield is strong enough, and rigidly mounted. Be
> sure it doesn't interfere with removing your rear wheel, or with
> re-mounting a dropped chain. And be sure it doesn't interfere with
> pants cuffs, or panniers.
>

The plan is that it will be inside the chainguard go almost low enough
to reach to the level of the lower chain run at its lowest reach.
That might intefere with removing the rear wheel, but not much.

>
> Do you have data on your chain life and the your mileage between
> re-lubricating? It would be nice to see a before-after comparison,
> especially if your chainshield is the only change you make.
>
I'm not that organized to give figures, but I'll know pretty definitely
if it makes significant improvement, will report back.

Can I post pics on this NG?

 

[[email protected]]

me wrote:
> On Mon, 06 Nov 2006 07:58:49 -0800, frkrygow wrote:
>
> >
> > me wrote:
> >>
> >> I am thinking of making an attatchment to my rear
> >> fender which will hang down from the front right
> >> hand side to divert water spinning off the downward
> >> side of the rear tire to keep it from washing the
> >> grease off the chain and coating it with crud.
> >>
> >> What do you think? Will this be an improvement from
> >> the point of view of chain maintenance?
> >
> > I think it might help some, but I'm not sure how much. The question
> > is, how much muck lands on your chain from that direction? Personally,
> > I don't think it's much. But YMMV.
> >
>
> I can't see where else the majority of crud would be coming from. The
> spray from the contact patch is gonna go mostly behind, whereas there
> will be a fairly constant stream flying off from the sides of the tire
> on the downward / forward section of the tire. Maybe I'm wrong.

I've always suspected the majority of the crud is thrown up by the
front wheel. Remember, we're not talking about great gobs of mud.
Most of what ends up on the chain is so fine, you can't perceive the
individual particles.

I'm sure my front fender stops a good bit. I normally use a mudflap
only when roads are wet, so I imagine there's a little cloud of fine
dust arising from my front tire's contact patch, some of which hits the
chain.


> Can I post pics on this NG?

No, but there are several photo hosting sites. You can put the pics up
on one of them, then give us URLs, perhaps processed through
www.tinyurl.com to get them down to a reasonable size.

- Frank Krygowski

 

[Wilfred]

[email protected] wrote:
> me wrote:
>> On Mon, 06 Nov 2006 07:58:49 -0800, frkrygow wrote:
>>
>>> me wrote:
>>>> I am thinking of making an attatchment to my rear
>>>> fender which will hang down from the front right
>>>> hand side to divert water spinning off the downward
>>>> side of the rear tire to keep it from washing the
>>>> grease off the chain and coating it with crud.
>>>>
>>>> What do you think? Will this be an improvement from
>>>> the point of view of chain maintenance?
>>> I think it might help some, but I'm not sure how much. The question
>>> is, how much muck lands on your chain from that direction? Personally,
>>> I don't think it's much. But YMMV.
>>>
>> I can't see where else the majority of crud would be coming from. The
>> spray from the contact patch is gonna go mostly behind, whereas there
>> will be a fairly constant stream flying off from the sides of the tire
>> on the downward / forward section of the tire. Maybe I'm wrong.
>
> I've always suspected the majority of the crud is thrown up by the
> front wheel. Remember, we're not talking about great gobs of mud.
> Most of what ends up on the chain is so fine, you can't perceive the
> individual particles.
>
> I'm sure my front fender stops a good bit. I normally use a mudflap
> only when roads are wet, so I imagine there's a little cloud of fine
> dust arising from my front tire's contact patch, some of which hits the
> chain.
>

>

I also think the majority of grit that gets onto the chain come from the
front wheel. I recently put some metal mudguards on my bike and I quite
often hear a pebble rattling up the gap between the tire and the
mudguard and see the pebble thrown out the front.

So if a pebble can do that then a lot of smaller grit must surely be
getting thrown off the rear of the front wheel , right onto the front of
the chainwheel.

Wilfred