Wednesday, August 09, 2006

Drivetrain Overhaul

With around 6wks left to our big Afan wkend, I figured it was time to get down to some serious spannerin' and fettle/overhaul my ride. As the chain was also getting past it's best, now seemed like a logical time to replace my entire drivetrain. Changing the gear now should also mean that I'll have some time to iron out any glitches and bed-in all the new bits.

So my ride time last wkend wasn't spent steamin' out on the trails :( but skimmin' flesh off me'knuckles within the cool garage.

Drivetrain replacement's; were 100% like for like, but not thru the lack of trying ;)
  • Chainrings (XT) - to overcome my dreaded Cannock induced, wet weather, granny ring climb chain suck. Although it's only a matter of time before it occur elsehwere and in all weathers.
  • Cassette (XT) - I did try and order a SRAM X0 (PG_990) cassette which unfortuntely wasn't in stock and I didn't like the number of loose rings on the X9 (PG-980) I received. With their tendancy to chew up alloy freehub carriers.
  • Chain (PG-971) - cleaned and then lubed with Chad's recommendation; T9 Boeshield. Hopefully it's better than Finish Line XC which washes off far too easily for my liking.
  • Rear Mech (X9) - after checking that the hanger was straight.
  • Shifters (X9) - I'd hoped that Chad might have some early 2007 units available, but alas no :rolleyes
  • Cables - Jagwire sealed jobbies replaced with a dose Teflon lube added for good measure.
Service items;
  • RP3 - I typically clean and regrease the air can every 6 months and this was the first time that I've ever had a grubby'un.
  • Freewheel (Chris King) - now using lighter/approved Teflon lube (Tri-Flow), which'll hopefully prevent drag experienced whilst back pedalling with subsequent cassette/chain de-railment.
A test ride had the drive train quieten down after a few miles with the shifters feeling slightly faster and defo lighter with new Teflon lined cables. I'm defo getting the hang of setting up this SRAM gear too, 'cos the cable tension didn't even need a tweak. A quick post ride check highlighted that the rear hub needed a little more pre-load, which was easily nipped up.

Tyres; Pleased with the results thus far, I was spurred on to change my summer-esque Racing Ralphs boots for my all mountain Bonty ACX's. But with a twist..:huh...this time I was going to ditch the tubes and go tubeless for the 1st time. So I set about;
  • removing the RRalphs - easy, 'cos they're not tubeless
  • stripping off the old rim tape
Cracking open a DT conversion kit then required the fitting of;
  • double sided tape - fiddly and time consuming
  • rim strip - a right wrestin' match with the elastic and rim parting company many times !
  • Bonty ACX - down right painful ! - these are absolute buggers to get onto my DT 4.1 rims and not a job I'd been looking forward to.
Seating the bead and pumping up the tyre with a track pump revealed a flaw in my approach...I should have used a new tyre ! This used boot appeared to have it's fair share of cuts and holes that now needed patching. So off the blighter came so that I could apply some tubeless patches. However, once into the Hutchinson repair kit it became clear that only 1-4mm holes needed patches and that some adhesive would suffice on my "bleeders" ! :x So, wrestle the tyre back on I did...eventually and with aching knuckles !

Adding 60ml of Bonty Super Juice was a simple task thru the clever removeable presta valve - which has gotta be easier than leaving a section of the tyre unhooked, as per many DIY kits. Adding 40psi revealed that the adhesive had silenced many of the leaks (phew) and the juice seemed to be taking care of the rest. A few slow turns of the wheel, at different angles, meant checking it again in the morning...where it had lost lots of air ! According to the instructions, this isn't unusual and I'll report back with an update shortly.

Oh gawd, I've still got the rear wheel to convert ! :o I'm not sure that my pinky's can take much more and my tyre levers are also looking "tired" ;-)


Dan Howell said...

From experience, I'd suggest adding the 60ml gloop in 2 or 3 sessions, because it took 3 fills before my tyres stopped going down over a period of a few days. So try 20ml in, close up, give the wheels a good spin (go out for a short ride, even), then return and leave a day or two - then if there's still air loss, another 20ml in and repeat as necessary...

Farqui said...

Now that appears to be sound advise 'cos I whacked another 50ml in last night, spun it, left it on one side and it's gone down less this morning.

I've not ridden it yet but am likely to add a bit more goo before tonights ride.

I also dropped the hoop in the bath, to id if the tyre was seated properly or if the rim strip was leaking. To my surprise the carcass of the tyre was leaking loads a tiny lickle bubbles with no major leaks.

Farqui said...

Oh, I neglected to say how many miles the ol'drivetrain had covered.

By my reckonin' it's been cranked for some 1,800 miles and abused in all weathers ;)

Excluding the chain, which has been replaced thrice and averaged approx 600 miles each. Less in the depths of a gloopy winter and longer when it's dry and bright ;)