How to Choose Colnago Y1RS Titanium Expander Kit: Shaft Size, Spacer Config, Assembly Guide

TiNEtech

4 ago 2026

The TiNE Colnago Y1RS titanium expander kit replaces 13 steel fasteners with Grade 5 Ti-6Al-4V counterparts — but the kit is not a one-size-fits-all product. The expander shaft must match your frame size, and the four handlebar screws must match your spacer stack. This guide walks through every sizing decision and assembly step so you get the correct configuration for your Y1RS.

Sizing & Selection FAQ

Question	Answer
Which shaft size do I need?	The expander shaft is sized to your Y1RS frame. XS frames use the shortest shaft (15.8 g in TiNE titanium, 33.8 g in stock steel). Each size increment adds 0.4 g to the titanium shaft and 0.9 g to the steel shaft. Larger frames actually save slightly more weight because the steel shaft grows faster than the titanium one — each step adds roughly 0.5 g extra savings beyond the XS baseline.
Which handlebar screws do I need?	Count the 5 mm spacers between your stem and the headset top cap on your current Y1RS. The kit provides six screw configurations, each containing two shorter and two longer M6 screws: 0 spacers: M6×25 (×2) + M6×30 (×2) — baseline weight 3.7 g per screw 1 spacer: M6×30 (×2) + M6×35 (×2) 2 spacers: M6×35 (×2) + M6×40 (×2) 3 spacers: M6×40 (×2) + M6×45 (×2) 4 spacers: M6×45 (×2) + M6×50 (×2) 5 spacers: M6×50 (×2) + M6×55 (×2) Each 5 mm step adds roughly 0.4–0.5 g per screw in titanium.
Can I mix shaft sizes or spacer configs?	No. The shaft must match your frame size exactly — a longer shaft in a smaller frame will protrude past the steerer and the headset preload will not engage correctly. The handlebar screws must match your actual spacer stack — shorter screws on a tall spacer stack will not reach the stem faceplate, and longer screws on a zero-spacer setup will bottom out against the steerer. Always order the configuration that matches your actual bike.
What if I change my spacer stack later?	If you remove spacers (lowering the stem), you need shorter handlebar screws. If you add spacers (raising the stem), you need longer ones. The other 9 bolts (expander core + limit + pin + cap + FD ×2 + seatpost clamp) are unaffected by spacer changes. Contact TiNE for replacement handlebar screw sets in a different spacer configuration.
What is the total kit weight for my configuration?	The published baseline is 49.1 g (TiNE) vs 98.5 g (stock) for XS shaft + 0 spacers. Adjust as follows: • Each shaft size above XS: TiNE total +0.4 g, stock total +0.9 g • Each spacer step above 0: TiNE total +~1.6–2.0 g (4 screws × ~0.4–0.5 g), stock total +~2.8–3.2 g So the savings actually increase with both frame size and spacer count.

Assembly Sequence: Installing the TiNE Kit on a Y1RS

The 13-piece kit splits into two assembly groups: the expander core (installed inside the steerer) and the surface bolts (installed on the frame exterior). Here is the recommended sequence:

Step	Component	Position on Y1RS	Key Note
1	Shaft	Inside steerer, above head tube	Slide in first, before ring and bolt
2	Locking ring	Around shaft, inside steerer	Sits over shaft, expands when bolt tightens
3	Main bolt	Through ring into shaft top	Tightening expands ring → locks to steerer wall
4	Limit screw	Headset preload adjust	Fine-tune steering bearing preload
5	Pin screw	Stem alignment pin	Aligns stem faceplate to steerer
6	Decorative cap screw	Top cap center	Holds the top cap cosmetic cover
7	FD mount screws ×2	Braze-on tabs at BB junction	M4, same position as stock
8	Seatpost clamp screw	Seat tube top opening	Clamps seatpost to frame
9	Handlebar screws ×4	Stem faceplate, front and rear	Match length to spacer stack (see sizing table above)

Install the expander core before the surface bolts. The shaft + ring + bolt must be assembled inside the steerer first, because tightening the main bolt expands the locking ring against the steerer wall — this creates the anchor point that the headset top cap and stem push against. Once the expander is locked in, install the headset preload (limit screw), then the pin screw, decorative cap, FD mount, seatpost clamp, and finally the four handlebar screws.

Stacking with TiNE's Y1RS Computer Mount

The Y1RS expander kit and TiNE's Y1RS titanium computer mount (#89) target different positions on the bike — the expander kit covers the steerer/headset/seatpost/frame bolts, while the computer mount sits on the stem faceplate. Because they share zero bolt positions, both can be installed simultaneously for compounded savings:

TiNE Y1RS Product	Coverage	Saved (XS+0 spacers)
Expander bolt kit (this product)	Steerer + headset + frame bolts	49.4 g
Y1RS computer mount (#89)	Stem faceplate, Garmin/Wahoo mount	varies vs stock
Y1RS balance weight set (#30)	Seatpost saddle mount	45.2 g
Full Y1RS coverage (3 TiNE products)	Steerer+frame+mount+seatpost	94.6 g+ (minimum)

Grade 5 Ti-6Al-4V, CNC machined, 8 anodized colors (gold, blue, rainbow, silver, black, pink, green, multi). 13-piece kit: expander core (shaft + locking ring + main bolt) + limit screw + pin screw + decorative cap screw + FD mount ×2 + seatpost clamp screw + handlebar screws ×4. Shaft sized per frame; handlebar screws matched to spacer stack (0–5). Designed specifically for Colnago Y1RS. Stacks with Y1RS computer mount and balance weight set for full-bike titanium coverage.

TiNE Colnago Y1RS Titanium Expander Bolt Kit — Selection & Assembly Guide
tinetech.com
49.1 g Ti vs 98.5 g Stock · 49.4 g Saved · 13-Piece · Grade 5 Ti-6Al-4V · CNC · 8 Colors · Colnago Y1RS · Shaft+Screw Sizing Guide · Stacks with Y1RS Mount+Balance