Rear light mounting problems

General cycling advice ( NOT technical ! )
Posts: 41
Joined: 2 Mar 2007, 6:37pm

Rear light mounting problems

Postby cricklewood_graeme » 15 Nov 2020, 4:20pm


For my regular weekly/weekend rides I have a wedge bag attached to my seat-post and no carrier. I wonder if anyone knows of a way of attaching a rear battery light to the mudguard or the seat-stays. Most lights I am aware of seem to be designed to be attachable only to the seat-post. I don't recommend the Newboler wedge bag BTW. It's difficult to mount and difficult to access. But that's for another post to this forum. :evil:

Posts: 4395
Joined: 8 Feb 2007, 12:37pm

Re: Rear light mounting problems

Postby tatanab » 15 Nov 2020, 4:26pm

Spanninga make a number of mudguard mounted lights, both battery and dynamo. Pixeo is a common model.

Posts: 6067
Joined: 5 Mar 2019, 5:42pm

Re: Rear light mounting problems

Postby Jdsk » 15 Nov 2020, 4:27pm

On the stay how about something like:
which should be better than a thumbwheel on a strap.

On the mudguard I've several times used a cut-down Cateye belt clip, with two holes: one for the bolt and nut and one for the locating peg so that it doesn't swivel:
Image ... elt%20clip


Posts: 42978
Joined: 4 Jan 2012, 6:25pm

Re: Rear light mounting problems

Postby Brucey » 15 Nov 2020, 5:12pm

bag should look like this when mounted

lamp can be mounted to bag or seatstay


Posts: 427
Joined: 16 Jan 2011, 8:36am

Re: Rear light mounting problems

Postby backnotes » 15 Nov 2020, 5:26pm

As above, you can mount lights on seat stays.

I have a battery powered Bobbin rear light on a rear mudguard. It's cheap and cheerful - not super-bright and has only one mode (i.e. "on") but on the plus side I can't leave it at home on the shelf by the front door. Indeed, it was a "distress purchase" when I found I had left my rear light at home!

It's mounted where the reflector normally goes, and includes a reflector.


Cheapest I can find is this one for £6.97 delivered that looks like the same light, but a different brand

User avatar
Posts: 12518
Joined: 24 Oct 2012, 10:43pm
Location: English Riviera

Re: Rear light mounting problems

Postby NATURAL ANKLING » 15 Nov 2020, 5:27pm

The trouble with mounting on the stay is that it's easy to get knocked.
Also on a tail bag it's difficult to get it to be pointing at the correct angle all the time.
and although it seems logical to mount it on the mudguard where the reflector normally it still gets knocked there too.
NA Thinks Just End 2 End Return + Bivvy
You'll Still Find Me At The Top Of A Hill
Please forgive the poor Grammar I blame it on my mobile and phat thinkers.

Posts: 30856
Joined: 9 Jan 2007, 2:44pm

Re: Rear light mounting problems

Postby thirdcrank » 15 Nov 2020, 5:31pm

I'm not up-to-date with Cateye mounts but they certainly used to do a chainstay-sized clamp to fit their standard rear mount. The problem used to be finding a stockest or even somewhere that acknowledged their existence. I think they have replaced the range of different-sized clamps with a single one-size-fits-all adjustable band

User avatar
Posts: 810
Joined: 6 Oct 2013, 10:20am
Location: Coventry

Re: Rear light mounting problems

Postby freiston » 15 Nov 2020, 5:36pm

I fashioned a bracket fixed to the mudguard using a bent L shaped plate (bracket) and fixing the lamp holder to it, leaving the seatstay clamp intact. I don't use it regularly - I put it there as a back-up to my rack-mounted rear dynamo lamp. Also, I sometimes use it when luggage is obscuring the dynamo lamp. I'm not sure that the bracket would last long with a light permanently mounted - I would worry about the mudguard stressing and splitting.
Disclaimer: Treat what I say with caution and if possible, wait for someone with more knowledge and experience to contribute. ;)

Posts: 721
Joined: 11 Jun 2015, 8:36pm
Location: Not the end of the world.

Re: Rear light mounting problems

Postby jimlews » 15 Nov 2020, 6:04pm

You can use an 'ahead' stem spacer, 1" or 1&1/8" and top cap.

Drill out one of the (two) rivets that mount the upper mudguard stay bridge and use a long bolt to secure spacer to mudguard. If your rear lamp is intended to affix to a seatpost, the rubber band will fit nicely around the stem spacer securely and out of harms way.

For example: ... 1-18-inch/ ... nch-black/

You will need to trim the bolt to length and secure with a 'nilock' nut.
Last edited by jimlews on 15 Nov 2020, 6:18pm, edited 1 time in total.

Posts: 139
Joined: 1 Sep 2014, 8:46am

Re: Rear light mounting problems

Postby wjhall » 15 Nov 2020, 6:05pm

The seatstay is a traditional mounting place, so the risk of getting knocked seems to have been thought small in the past. The Rixen item looks rather neat.

I assume that in the artisanal mudguard version the seatpost clamp has been left in place for some extra security around the bracket. Otherwise it can be taken off, and the remainder screwed directly to a bracket. The stresses on the mudguard presumably depend how far you can spread them with a form fitting plate on both side.

Posts: 106
Joined: 21 Aug 2020, 7:01pm
Location: Stockport

Re: Rear light mounting problems

Postby GeekDadZoid » 15 Nov 2020, 7:31pm

I have two of the Aldi silicon led lights on my seatstays one on each side.

Makes sense to me as a place to mount them.

User avatar
Posts: 5319
Joined: 7 Jan 2007, 9:29pm
Location: Gloucestershire

Re: Rear light mounting problems

Postby andrew_s » 15 Nov 2020, 9:27pm

I'd recommend one of these mudguard mounted lights (B+M Secula) ... -Permanent

There's also this mount that allows 50 mm rack-mount rear lights to be fitted to the mudguard. ... t-bracket/
(DIY of something similar is fairly simple, provided that you have a suitable chunk of aluminium)

Note that you should take care to get your rear light aimed pretty close to horizontally.

It's fairly common to see lights aimed upwards at around 10° or so, which looks great when checked from 2 or 3 m behind the bike, but because most LED lights have a fairly narrow beam, generally looks much dimmer when viewed from 50 m behind, which is about the distance you want a car driver to find your light obviously bright.
For example, I often see the Cateye LD610 mounted vertically on a seatstay. It looks good, and is low-profile enough to avoid knocks well, but on most bikes it's not possible to aim it correctly, as the mount pivot point isn't far enough out from the seatstay to allow the light to be tilted enough, without the lower end of the light hitting the seatstay.

Posts: 30856
Joined: 9 Jan 2007, 2:44pm

Re: Rear light mounting problems

Postby thirdcrank » 15 Nov 2020, 9:39pm

andrew_s wrote: ... Note that you should take care to get your rear light aimed pretty close to horizontally. ....

^^^^ Yes ^^^^^^^

LED lights are very directional. Whatever arrangement you settle on, I'd recommend propping up your bike as near vertically as possible, or getting somebody to hold it - in the dark, of course - then check what it looks like from 50-100 yards down the road.

Posts: 1675
Joined: 10 Oct 2009, 8:20am

Re: Rear light mounting problems

Postby tim-b » 16 Nov 2020, 6:02am

Mount the bag in a better way and you might have enough seat post to use, I've got two lamps on here although the bag is much smaller...


User avatar
Paul Smith SRCC
Posts: 1111
Joined: 13 Feb 2007, 10:59am
Location: I live in Surrey, England

Re: Rear light mounting problems

Postby Paul Smith SRCC » 16 Nov 2020, 10:11am

Sadly not many quality rear lights are set up to attach to a rear guard.

I still use a Cateye TLAU100 in place of a the reflector as I referenced in a thread way back in 2008, you may still find one on ebay, I've just looked and found one easy enough.
cateye TL AU100.jpg

You can always fettle many to the mudguard eye as well
Light to mudguard eye.jpg
Light to mudguard eye.jpg (48.5 KiB) Viewed 461 times

For those needing new guards the Bontrager NCS Mudguard Set can take their own rear lights, the Flare RT is impressive, cheaper but still good is their Flare R; both USB-rechargeable, they have a front versions of both
integrated Blendr light mount.jpg

I personally use the cheaper 'R' models as day time running lights in the summer and as helmet lights in the winter, their Blendr system mounts to some their helmets
Last edited by Paul Smith SRCC on 16 Nov 2020, 10:48am, edited 2 times in total.