M:Part Seat Clamp with Rack Mounts

Customer Reviews (2)
4.5 / 5| Write your review
£12.99 Please note this product has selling restrictions to your country. was
Manufacturer : 
SJS Cycles part number : 
Manufacturer part number : 
Got a bike with no rack mount, but want to fit a rack ?
The rear of this seatclamp has bosses which allow a rear rack to be securely fitted
31.8 mm internal diameter
Ideal for bikes with small frames and no rack braze-ons
Also suitable for bikes with wishbone rear stays
Matte black finish with stainless steel hardware
Only avalible in 31.8
Product Reviews (2)
Questions & Answers (5) Q & A
Download File  
Product Reviews (2)
Overall Product Rating 4.5 / 5
Neat & Easy
By Anonymous
06 Apr 2017
5 / 5
I recommend this product
Proseasy to fit, neat
Very easy to fit - take seatpost out, take old clamp off, drop new clamp on, re-insert seatpost.
Much neater and easier solution than using p-clips on the seat stay.
Remember to use the diameter of the seat tube, and not the seat post to select the size of clamp you need.
By Bill Wilson
22 Jun 2012
4 / 5
ConsI found it awkward to fit
ProsDoes what it says on the packet
This item came in record time from SJS and although it is the same size as my seatpost. I have a Carrera Ltd Edition 26 inch Hybrid. At the moment I cannot seem to fit it without some kind of tool to spread the opening. My seat post is the same size and wouldn't fit without trying to spread the jaws.I will figure this out. This is my only problem .
Questions & Answers (5)
Will 16mm M5 bolts, with washers, be suitable to attach a standard (Topeak) rack fitting?
10 Jun 2022
it depends on how thick the stays are, M5 bolts are the correct thread but I'm not sure what length you would require.

If you can email [email protected] with your query and link to both products in question we can check this for you.

Thanks, JK 10.06.22

Clamp material and comparison
18 Oct 2021
Would it be suitable for use with an Ortlieb Rack 3 or Tor Tec Ultralite Alloy Rear Cycle Rack?
Also what is it made of and how does it compare with the Wave and Passport versions you sell? e.g would either of those be more suitable?
Thank you for your enquiry, it is alloy and should be fine with those racks.

WD 18/10/21
Is this supposed to clamp on the frame or the seat post.
19 Jul 2021
Hi, Will you please advise whether this can be clamped to either the frame or seat post, so that I can determine which diameter of clamp to order. Also can you please advise how the top tube diameter should be measured i.e. internal or external diameter at the point where the existing clamp is fitted.
Thank you for your enquiry, it fits to the bike frame, you will need the external diameter of the seattube

WD 19/07/21
Measurements of 29.8mm-Version
11 Nov 2019

I need two measurements of this seat clamp with 29.8mm diameter:

1. Outer width at rack mounting points.

2. Drop/distance from center of the clamp bolt to center of the rack mounting point.

Thanks and best regards.
Hi there,

The outer with of the rack mounting points is approximately 40mm and the distance from the clamp bolt to rack mounting is approximately 22mm.

Seat Bolt Size
13 Jun 2017
What is the size of the seat bolt? M6? And length?


The seat bolt in this clamp is M5 x 18mm.