We are sure that having given the Giant VT a number of 10 scores over the last three years there are more than a few out there. Knowing Brit riders and their penchant for riding in atrocious conditions, these bikes have probably taken a fair bit of abuse, and the pivots could probably do with some TLC.
The bike we’re using for this service is a 2005 VT frame we’ve had on long-term test. It has developed play in the lower shock bushing, which can be felt as a knocking when lifting and dropping the rear wheel, plus the bearings seem a bit worse for wear. To check the bearings, remove the shock and rear wheel and then compress the swingarm; it should rotate smoothly and without play. Even so, further dismantling of the linkages may be necessary because only by rotating the bearing through 360 degrees will any pitting or roughness show up.
It may sound like the VT would be easy to service because it’s a single pivot, but the shock is driven by a linkage so it has as many pivots and bearings as some four-bars. Various pivot and bearing kits are available — the triangular pivot arms with bearings installed and all the fitting bolts are £50. The horizontal dog-bones with bearings and bolts are £50. Bearings and bolts for both are available separately for £25. Shock and main bearing/bolt kits are £5 and £25 respectively; the latter also includes a new hanger. There’s also separate kit for the 2003 models, but it’s worth contacting Giant or a dealer on requirements if you’re unsure about what kit you require.
Replacing the bulk of the bearings and all the links is going to cost you over a £100. The bearings and bolts on their own are around £55. Add the tools and you’re looking at another £30. It may be worth getting a Giant dealer to do this service because they should have all the tools in stock and if they crack any of the bearings or damage one of the links they will have to replace them. The repair is also guaranteed for 12 months. At the end of the day it’s your call, but if you decide to give it a go this service is well within the abilities of most home mechanics.
To help us with this month’s step-by-step we called on the help of Mark Hill, Giant’s resident warranty/technical bloke.
Tools for the job:
5, 6, 8mm Allen keys / 10mm spanner / Giant bearing press £5-7 / Grease / GT85 or WD40 / Adjustable spanner / Crank extractor / BETD shock tool £24, call BETD 01782 629462
1 Remove the crankset with whatever tool you need. Then remove the rear wheel.
2 To check for play in the bearings compress the back end and flex the swingarm from side to side. You should be able to feel any roughness.
3 Using a 5 and 6mm Allen keys loosen the pivot bolts. Make a note of the orientation of the bolts and the small steel washers and sintered bushings.
4 Once you’ve removed the bolts examine the surfaces for wear. Any deep grooves or really polished areas and the bolts need replacing, as these can lead to possible failures.
5 There’s a small worn section on the top of this pivot plate; That’s a sure sign of play in the bearings.
6 A full-length pivot bolt runs through the main bearing. This can corrode and seize inside the frame. If it already has, undo the bolt two turns and tap it with a soft mallet.
7 Check the bearings for any roughness — those on our frame were indexed and needed replacement. Any rust spots are also a good indication of contamination.
8 Giant’s bearing puller/bearing press is a simple collar with a nut and bolt. The large U-shaped washer goes on the back, the small one on the front.
9 The main pivot bearings in our frame were seized. Mark fitted the puller back to front and moved the bearing a tiny amount to break the seal before pushing it out as normal. It took a lot of brute force and broke the bearing into several pieces.
10 Replace all the bearings as necessary then clean up the bearing surfaces with GT85 or similar.
11 Using a BETD bushing press remove the old shock eyelet bushing and press in a new one. Refit the shock and tighten the top mount to 9-11NM, the bottom 6mm to 10-12NM.
12 Reinstall all the plates and give all the bearings a smear of grease (wipe off any excess). You can do this periodically to stop water ingress and keep them running smoother for longer.
Remember the fat end (with the two mounting holes) of the triangular pivot plates face downwards. Torque these bolts to 9-11NM.
Also the fat end of the dog-bone faces the rear of the bike. Again torque these to 9-11NM.