Sunday, 16 February 2020

Replacement headset and forks

Shelley's bike had two issues. It had started to pull to one side and the steering was very rough. In addition the forks were not performing as they should.


Today Dean and I fitted a new headset and new forks. Mainly I watched and learnt while Dean fitted them.


The forks came out easily. The bottom bearing came out just by pulling however the top bear fell apart and the casing had to be levered out.


That bearing probably had a lot to do with the poor performance Shelley had been experiencing.


Getting the old bearing cups out was tricky. I tried with a bearing cup removal tool and just managed to bruise my knuckle. Dean removed them by drifting them out with a punch a little bit at a time, round the edge.


To fit the new one, we put the cups in the freezer for half an hour and used a heat gun to warm the head. We were not sure how much that helped but did it anyway.

Inserting the cups straight was the tricky bit, even with a bearing press.


We cut down the fork head tube to the same length as the forks that had been removed.



I used a star nut inserting tool to get the star nut in to the end of the tube.




To fit the crown race on to the fork crown we heated that slightly and used a home made tool, made out of a large aluminium tube, to seat it. The end was ground down, to fit over the angle on the crown race.



We greased the bearing cups and inserted the bottom bearing and the fork tube, followed by the top bearing, the split upper race, the spacers, the stem and finally tightened the top cap to pull it all together.




Fitted the brake and the wheel.

Once on the ground, Dean straightened the handlebars and tightened the bolts on the stem.

Job done.

We set the fork damper up for Shelley and she took it for a test ride up the driveway. She was very pleased with the improvements.

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Merida ONE-TWENTY 7.800 model year 2015

Forks: Taper tube 1"1/8" to 1.5"
FSA Headset
Frame cup diameters:
Upper: 44mm (43.7mm measured. 44.1mm cup fitted)
Lower: 55mm (54.9mm measured. 55.1mm cup fitted, FSA H5064)
Bearings:
Upper: 41mm O/D (40.9mm measured) 7.3mm thick. 45 deg outer and 36 deg inner angle. (FSA MR0401-1/8)
Lower: 52mm O/D (51.7mm measured) 7.5mm thick. 45 deg outer and 36 deg inner angle. (FSA MR019 1.5)



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Forks
SR Suntour Aion 150mm travel. 27.5" wheel. 100x15mm axle.


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Fitting a tubeless bike tyre

As mention in a previous post, the hub on my bike made a grinding noise and the freewheel had a large angle between teeth. For those reasons I have changed the back wheel.


I am a fan of tubeless tyres. Mainly, I like being able to ride without having to stop for punctures.

First job was to fit the tube tape to the rim. The tape supplied with the Hope wheel was a thin plastic which was fairly stiff. I found this a bit of an odd choice because it has to curve in both directions and this tape didn't want to do that.


I fitted it as best I could, working round the wheel to get as many of the bubbles out as possible. Mainly I made sure I had sealed round every spoke hole. I used a cloth to keep going round the rim and attempt to bend the tape to the shape of the rim.

The result was not as tidy as I was expecting to be able to achieve but eventually had to accept I wasn't going to get it any better.




I cut out the hole for the valve and tidied up the edges, as best I could.



I tried to get the tyre off the previous wheel without loosing too much Stan's Tire Sealant. The tyre was easy to get off with a couple of tyre levers. I lost about half of the tyre sealant, transferring the tyre to the new wheel. It made a mess on the workbench so I ended up putting a wadge of paper towel under the tyre to sock up what came out.

I had watched the Stan's video on how to fit tubeless tyres and was following their suggestions for the most part.


I got most of the tyre bead inside the wheel rim but before closing the last bit, I sloshed in a fair quantity of Stan's No Tire, Tire Sealant, to the bottom of the tube. I'd guess, over 100ml (about 4 oz).

I used two tyre levers to get the last bit of the tube lip inside the wheel rim. I lost a bit of sealant doing that but not too much. I rotated the wheel a couple of times to spread the sealant about.

From what I have read, getting the bead to seat is the bit that people have trouble with. I have a full size car air compressor, which makes that job fairly trivial.


I have modified an air blower, with a thin nozzle and a rubber grommet. I set the air compressor to near it's maximum 90 psi (6 bar).


I inflated the tyre without the valve core in, so that I could inflate it as quickly as possible. To my mind this helps to get the beads to seal on the edges of the rim, which helps to inflate the tyre.


I rapidly inflated the tyre to it's maximum 60 psi (4 bar) and checked round both sides to see if there was any sign of leaking. My own tip is to let the tyre deflate and see where the rim comes away from the bead and inflate the tyre again until I am sure the bead has seated. I pulled on the side walls at any point that did not look completely even.

I was pleased that my poor looking rim tape was sufficiently sealed to hold the air in.

As I had done this without a valve core, the tyre deflated when I released the air blower. As that was obviously going to happen, I made sure that the tyre was not pulled off the rim, by laying it horizontal.



I fitted the valve core and inflated it again. This time finishing off with my normal track pump which is easier to fine tune the pressure.



I left it for a while, over pressure, at 3 bar (about 40 psi) to make sure the tyre was holding air and then once I'd finished fitting the brake disc and cassette, I dropped it down to about 2 bar (about 30 psi).


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Saturday, 15 February 2020

Tidy up from the storm

Saturday had a few jobs to do caused by the storms.



First cut up a tree that came down the previous weekend.


When I caught my head on the rose, we realised that a tree at the end of the drive, was precarious.


It was being held up by another tree so we had to use Shelley's car to tow it down.




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Wednesday, 12 February 2020

Bike wheel workstand

I wanted something that could support my bike wheels while I work on them.
I looked at budget truing stands but most of them were too small for 29" wheels or not what I was looking for and still more costly than I thought they should be.
Some of the more expensive truing stands would have done the job but they are over kill for the few times I am going to need a wheel supported off of a bike.


I screwed a few bits together to make what I needed.




Steel angles and some timber with removable aluminium drop in cups. It's setup to fit up to 148mm wide axles but I could fit spacers, for even wider wheel's, if that was ever necessary.


I've used a 5mm threaded rod and some spacers to make an adjustable axle.


I've used cones which will seat and centre inside 12mm, 15mm and probably 20mm axles. I was going to 3D print the cones but I came across exactly what I needed, in aluminium, on ebay. I can just reverse the cones when working on wheels intended for QR skewers.

The stand is designed to fit in the vice on my workbench.

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Tuesday, 4 February 2020

141 QR hub bike wheel

I am told that one of the areas that manufacturers can skimp on to reduce the price on lower budget bikes, is the wheels. I have already discovered that could be the case on my bike. It's less than 6 months old and already the rear hub sounds rough and grainy.


The bearings, in my rear wheel, are loose ball, cup and cone. Serviceable but obviously vulnerable to the ingress of grub. Not only that but the freewheel has a large angle before it engages. I'd noticed, while riding, that I had to rotate the pedals quite a way before I could get them in to a semi-comfortable position to pull away. I hadn't thought much about it until I looked closely at Shelley's and Dean's bikes. As I rotated the cassette, I noticed how much smaller the ratchet angle was. It's obvious to me now that better hubs have smaller angles before the ratchet engages.

The rough bearings and the poor freewheel, combined, has led me to want to change the rear wheel for something better. Something with sealed bearings.

My Giant Stance came with a rear wheel with a 141 QR (Quick Release) hub. This is a relatively new size and I could not find a pre-built wheel, stocked by any of the major suppliers that I looked at.

I did a lot more searching and, with a bit of knowledge, it's not as tricky to get new wheels as it would first appear. I could easily have had them custom made however, it is also possible to get an off the shelf option at a more acceptable price. The 141 QR fitting is a boost 148x12 TA (Through Axle) hub with the end caps replaced for the same QR end caps fitted to 135 QR hubs.


Not all hubs have replaceable end caps but there is a good choice that do. I found several well respected models and a video showing exactly what I wanted to do. I opted for the Hope Pro 4 hub because a complete rear wheel using them and the end caps were stocked by Chain Reaction Cycles.


It's an easy job to pull off the end caps and swap them for another size.



It just needed a little bit of gently leverage to pry the end caps off. The new ones just push on and I now have 141 QR wheels with a better quality freewheel hub.


I've fitted it to the bike to check it fits. I just have to seal the rim, swap over the tyre and inflate it to pop on the bead. After that, I'll add a couple of small bottles of Stan's No Tire, Tire Sealant and re-inflate.


I should then have a much better performing rear wheel that will need less servicing.

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Summary:

142x12mm TA converted to QR end caps = 135 QR
148x12mm TA converted to QR end caps = 141 QR

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QR141, QR 141, 141 QR, 141QR.