M:Part Carbon Fork Expander

Customer Reviews (5)
4.8 / 5| Write your review
£16.99 Please note this product has selling restrictions to your country. was
Manufacturer : 
SJS Cycles part number : 
Manufacturer part number : 
Headset tensioning top cap expander system for use in carbon composite steerer tubes
Expands inside the steerer tube
Causes no scoring or marking inside the steerer
Recommended for carbon composite steerer tubes
Anodised black finish with a lacquered carbon fibre top cap
Great looking and extremely functional
Product Reviews (5)
Questions & Answers (15) Q & A
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Product Reviews (5)
Overall Product Rating 4.8 / 5
Perfect for the job.
By Niven Chalmers
27 Feb 2018
5 / 5
I recommend this product
ConsNothing really.
ProsGood construction and a good price.
1 inch carbon fork steerer expanders are almost impossible to find these days, and this one is perfect for the job. Also for a good price and quick delivery from SJS. Thanks.
Perfect fit for Pesenti Fiandre
By Pavel Kosarev
29 Sep 2017
5 / 5
I recommend this product
Diameter 18.9 mm
Great Service From Sjs
By Anonymous
20 Jun 2017
5 / 5
I recommend this product
ProsFast shipping. Great piece of kit
It's not easy to find a 1" carbon fork expander. The M-part one is just great, with a perfect finish all round and a cool carbon ahead cap with minimalist logo.
Overseas shipping from SJS was fast and hassle free.
Direi Che Fa Quello Che Deve Fare
By paolo
04 Mar 2017
5 / 5
I recommend this product
Il prodotto è della misura giusta per una forcella da 1 pollice e fa quello che promette. L'expander mi sembra di buona qualità, anche se il tappo di chiusura è diverso rispetto a quello raffigurato in figura
Good Quality Product At A Reasonable Price
By Nick Thorpe
24 Jun 2016
4 / 5
I recommend this product
ProsGood quality product, will fit a range of different sizes of steerer
Needed a replacement to fit a 22 mm internal diameter carbon steerer. This was very easy to install and looks good too.
Questions & Answers (15)
What is the largest I'd the 1 1/8 will fit. Mine is 23.9mm.
23 Nov 2022
Thank you for your enquiry, unfortunately it will only fit upto 22.2mm
Regards. WD 24/11/22
Hi, will the 1 inch carbon fork expander fit a carbon for that is 19.8mm internal diameter?
10 Aug 2022
This should fit any Carbon fork with any 1-inch external diameter, the ID is less of an issue as it is size adjustable to account for various wall thicknesses.

JK 11.08.22
Can I use the 1 inch version with a Colnago Force carbon 1 inch fork?
07 Jul 2022
Based on your previous replies I purchased your 1 inch version expander to use with a Colnago Force carbon 1 inch fork. It doesnt fit.

In your replies to similar questions you have stated different diameter of the expander. 18.8mm and 19.8mm.

If it was 18.8mm it would fit a Colnago 1 inch fork but it does not.
Uncompressed, the OD measures 19.8mm,

JK 08.07.22
What is the total length of this item inside the steerer? Ie what clamping length does it support?
13 Apr 2022
Thank you for your enquiry, it is around 35mm total length that would be inside the steerer.

WD 14/04/22
i have a 1 & 1/8 fork with internal diameter 22mm - which product should I buy? the 1 inch or 1 1/8?
04 May 2021
Thank you for your enquiry, the 1 1/8 will be correct

WD 05/05/21
Can I use this with Columbus Muscle 1" Forks
21 Feb 2021
Inner diameter of steer is 19.2 mm.

Thank you for your enquiry, yes will fit fine it measures 18.8mm

WD 22/02/21
Can I use this with Colnago C40 1 inch fork? steerer tube inner diameter is about 3/4 inch or 19mm
02 Jan 2020
As long as you select the 1" option, yes this should be good.

Thanks - 03/01/20
Hi, the 1inch version fit with a inner tube 19.5mm? Thanks. What is the minimum diameter?
20 Jan 2019
19.8 mm
Measured diameter of this fork expander
MPart Carbon Expander
25 Jul 2018
Hi I need a expander for my 1”Mizuno 700c Carbon Steerer forks the internal diameter is 18mm would this work or can you advise an alternative..
Cheers Richard
Hi there,

Unfortunately the smallest that this will fit is 20mm, and we do not sell anything else that would be suitable im afraid.

Will it fit a stem that has its own top cap?
10 Apr 2018
I have a Merida Warp TT bike and it has a 1 in steerer tube fork (20.5 mm approx inner diameter) and a special stem with its own steerer tube top cap. Does this M:Part expander use a special cap with internal threads (like the FSA model) or would any regular top cap and bolt work? I would simply use the Merida cap and bolt. A picture of the expander with the top cap removed would greatly help.
Hi there,

This uses a standard top cap/nut not an internally threaded one.

Hi, will this a fork with an internal diameter of 20mm?
03 Feb 2018
Hi there,

The smaller option will fit 25.4mm +- probably only a few 0.1mms!

What is the weight of this expander? Thankyou
07 Sep 2017

The 1 1/8" expander weighs 40grams.

hi can you tell me what the smallest id this will fit cheers .
04 Aug 2017
Hi, the 1 inch is 20mm, the 1 1/8 inch is 22mm. Thanks
Hi, I Have A 1 Inch Carbon Fork, But The Inside Diameter Is 20.0Mm. Will This Expander Fit?
31 May 2016

This expander will be suitable for use with your forks.

What Internal Diameter?
22 Jun 2014
my fork is a 1 1/8 inch, but has an internal diameter of 22mm. Will this fit?

Yes, this will fit your forks.