VFR Caliper Rebuild

After having a go on Helen’s VFR last year I realised how bad the brakes on my VFR had actually become. So I decided that the constant glazing of the front discs was most properly due to the pistons binding. The discs are quite pitted as well but I really don’t want to be buying some new discs when I am likely to replace the VFR next year. So I decided the best course of action was to strip down the calipers and replace all the seals and then to fit a new set of brake pads to the fronts.

I removed all the brake calipers and then slightly ejected all of the pistons. I then sucked out all of the brake fluid with a brake vacuum pump. I disconnected the banjo bolts and then ejected the pistons from the caliper bores with compressed air. All of the pistons were slightly pitted but looked in good condition otherwise, bar one off the rear caliper that was heavily scored. The caliper bores and seals looked in good condition, so I cleaned the bores and fitted the new sets of seals anyway. I also decided to replace the heavily scored rear caliper piston. I then re-assembled the calipers and refitted the pads and re-installed all the brake pipes and banjo bolts. I then refilled the brake fluid and sucked it through with the brake vacuum pump. I would advise that you purchase one if you intend to do this job as you will struggle to get the fluid through without one. Once the fluid was through it was time to bleed the brakes, I started with the fronts as you can do this yourself. Do the left caliper first (top bleed nipple) then the right hand caliper, you can now seal the front brake reservoir.

Now for the pain in the arse rear circuit, you will need a second person for this. You need to remove the front left caliper and put something in between the pads to stop the pistons being ejected. You then need to bleed at the proportional valve by the battery, while someone activates the secondary master cylinder pushrod at the left front caliper. Once that is clear it’s time to bleed at the rear caliper middle bleed nipple, while again activating the secondary master cylinder pushrod. The Haynes manual advises you to remove the caliper and re-mount it the other way round on top of the disc, to make the bleed nipples accessible. I found even doing this I was unable to get all the air out. The solution is to remove the caliper and place something between the pads and then rest the calliper on top of the disc with the bleed nipple pointing directly upwards, only then did I manage to get all the air out. Once that is done you need to bleed the rear pedal circuit. First is the servo proportional valve (right side under seat by fuel tank), then the rear outside bleed nipple and then the front left lower bleed nipple. If after this the rear pedal is still a bit spongy there is more than likely still air in the secondary master cylinder circuit. Unfortunately due to the MOT having lapsed on the VFR I am unable to test the brakes properly till I have taken it in, I will update this post after that point.

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Wales Season Opener

Apart from Boxing Day this is the first time since last November that we have been out on the bikes, as the weather and icy conditions haven’t been very favourable. We met up with some of the guys from NUKB at Lymm Services for around 9am. I was out on the ZX-9R as the VFR’s MOT has currently lapsed and I am in the process of rebuilding the callipers as the front discs keep glazing over.

We left Lymm Services on the M56 and the got off at Jct10 to join the A49 to Whitchurch. We continued on the A49 for a while before turning right onto the A534 to Wrexham. We skirted around Wrexham and joined the A483 and headed South for a short distance before getting off the dual carriageway and joining the A525 towards Llandelga. Somewhere along this road one of the guys picked up a puncture which ended up splitting up our group. I continued on the A525 and then joined the A5104 at Llandelga which I took to the A5. I then turned right onto the A5 which I only followed for a very short while before turning onto the A494 to Bala. The road to Bala is a good one but is often filled with lots of traffic, even at this time of the year. I arrived in Bala and stopped in the public carpark on the left as there are toilets there.

I then left Bala and continued on the A494 to Dolgellau, this part of the A494 is even better and as some of the traffic usually stops at Bala it is usually a little bit quieter. An alternative route to Dolgellau is to take the A4212 from Bala past Llyn Celyn to Trawsfynydd. This is a very nice road with lots of different types of scenery. You would then turn onto the A470 and follow that to Dolgellau, this part of the A470 is a bit boring as it is very straight road. I stopped for lunch at Dolgellau where I expected the other guys to catch me up, but due to the puncture they had stopped at a farm café back on the A5. I was obviously now miles away from there so it wasn’t really feasible to head back there.

So I left Dolgellau on the A470 heading towards Mallwyd but soon turned off and joined the A487 to Machynlleth. The A487 is a fantastic road and is also fairly quiet so you can usually get a decent run down it. The road starts off with some faster more open corners before you climb up to the top of the pass and then drop down on the other side. The way down is a twisty fast affair we a huge drop off to the right hand side. Just after Corris the road changes again as you get into the trees and follow the very twisty last part Machynlleth. Due to lots of double white lines in this area if you get stuck behind traffic it will be spoilt, so I would consider stopping and allowing yourself a clear run if possible. I arrived in Machynlleth and stopped at the fuel station to fill up, it is just after the railway bridge on the right hand side.

I left Machynlleth on the A489 and then took the A470 towards Newtown. This part of the A470 is certainly worth doing and is pretty open and you can usually get a good run at it. At Caersws I joined the A489 and headed over to Newtown, unfortunately it was too late to head South on the fantastic A483 to Crossgates. So instead I headed North and followed the A483 through Welshpool and Pant towards Oswestry. This part of the A483 is really only a means to and end. As it is quite boring in places and usually full of a lot of traffic. I stopped at Oswestry Services to see were the other guys were currently. I got a text back to say they were at Whitchurch and would wait for me to catch up.

So I left Oswestry Services and headed on the A495 through Whittington and Ellsemere and over to Whitchurch. Although not a challenging ride the A495 is very scenic for most of its length. I then joined the A525 and A41 to met up with the other guys at Lynns Raven Café in Whitchurch. We then headed home via the A49, M56, M6 and M62/M60.

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