I’ve installed most of the parts onto the bike now, but there were a few hiccups along the way.
Firstly it turns out that Hollowtech 2 cranks are fairly snug fits for the bearing sleeves. As a result didn’t realise that I hadn’t pushed the crank all the way through to the other side.It was only when I was about to put the pedals on that I realised the chain ring seemed to be a long way out from the side of the bottom bracket.
On top of all that I should have known something was wrong as the front dérailleur was clearly misaligned. It was popping back and forth around the innermost front cog which would make it impossible to shift gears, and a quick test told me that there was no way it could shift the chain to either of the outer rings. To test my worries by hopping into the saddle and dangling my feet roughly where the pedals should be. The positioning definitely didn’t feel very natural, and my right leg was perfectly position to get slashed to hell by the chain ring with every turn of the pedals.
As an experiment I gave the crank a quick, and thoroughly unscientific, dunt with my foot to see if it was properly installed and lo and behold it popped through about an inch and a half and settled into a far more sensible looking position.
Second thing I found was that my fancy new Shimano rear cassette had a set of bolts which emerged from the back of it to help secure the various cogs together. These bolts were rubbing against the plastic freehub protector which prevents the chain leaping off the largest rear cog and wrapping itself around the spokes of the rear wheel. So long as the rear dérailleur is properly aligned and adjusted there shouldn’t be a problem, but I’m still a bit wary.
The only thing left to do is try it out.
After several unforeseen delays I finally got my hands on the replacement cranks that I ordered for my bike. Unfortunately, and with the perquisite Ayrshire level of hubris, I made the mistake of assuming that I had all the necessary tools to remove the old cranks and fit the new ones.
It turns out that the tool kit that I have doesn’t have a tool capable of removing the splined lock rings on the Truvativ sealed bottom bracket that came with my bike. I didn’t notice the problem to begin with because visually the installed bracket seems to be similar to the ones that belong to the ISIS system. I assumed that the tool for the ISIS system that I do have would fit it no bother. It turns out that the axle on the Truvativ is several millimetres wider in diameter than the ISIS ones and as a result the tool I have won’t fit over it to reach the ring itself. It’s next to impossible to remove the bottom bracket without the appropriate tool.
Fortunately it seems that it’s easy to come by these tools as all the major bike shops in town seem to sell them. Naturally though the damn thing is between ten and twenty quid which seems like a lot of money for what’s basically a funny shaped socket attachment.
Kids the moral of this story is: check what tools and equipment you need BEFORE YOU START.
I got an email the other day from Evans Cycles saying that they’re running a special 10% off on everything until the 3rd of January. To take advantage all you have to do is put in a voucher code “SAVE10″ when you order online. They’re also freezing the VAT rise from 15% back to 17.5% for the foreseeable future which means that it looks like as good a time as any to by the parts I need.
I’ve ordered exactly the bits that I mentioned in my previous post, and with the 10% discount I’ve already saved about nineteen quid off the normal price.
Shimano HG93 Chain (OEM) £17.99
Shimano M770 XT Cassette – 9 Speed (OEM) £39.99
Shimano M770 XT Hollowtech 2 Chainset (OEM) £127.99
Total less 10% discount – £167.37
Hopefully I should have them in the next week or so, and then the adventure of getting them fitted to the bike can begin.
My bike is still out of action, and it’s starting to get me down. I know logically that we’re getting into the depth of winter and that I probably wouldn’t ride it that much if it was fully operational, but that doesn’t stop me illogically wanting to ride it anyway.
I’ve been reading reviews on various mountain bike websites, as well as trawling through the parts sections on Evans Cycles, Dales Cycles and the Edinburgh Bike Coop’s websites. From what I’ve read it seems that the old maxim holds true even for bike parts: “buy cheap, buy twice”. All three shops have an extensive collection of parts to suit every budget, but as I seem to have already been stung by what amounts to a fairly cheap FSA OEM crankset I’m not anxious to buy a budget set just for the sake of saving a few bucks.
I’ve just about settled on a Shimano M770 XT Hollowtech 2 Chainset which is at the upper end of the market, but not into the ridiculous money range. At the time of writing Evans are currently selling the OEM version for £127.99 and the original retail version for £164.99. As both versions include the bottom bracket and all the other required parts the only difference appears to be in the packaging.
As I said in my earlier post it’s not just the front chain rings that are a bit worse for wear. The rear cassette has suffered a bit of damage as well, either as a result of the front rings causing the chain to slip, or as a result of a damaged chain. Currently I’m considering the Shimano M770 XT Cassette which is an exact match for the M770 XT chainset that I mentioned above. Again the cassette is available in an OEM version for £39.99 or a retail version for £56.99. I’ll admit that I haven’t put as much research into the cassettes as I have with the chainsets, but I can’t see there being too much to chose between them.
It goes without saying of course that any replacement cassette and chain ring will have to be accompanied by a new chain to match. To be honest there doesn’t seem to be much of a difference that I can see between the various chains, but the Shimano HG93 Chain at £17.99 on Evan’s site seems an OK choice to go with the M770 XT parts that I’ve spoken about.
At the moment these three parts will set me back £185.97 in total if I go for the OEM versions. Then it would be simply a matter of getting them attached to the bike and adjusted… Simple…
Out of the blue my bike has developed some kind of problem with the gears. It seemed to be fine when I was riding along on the flat or down hill, but as soon as I shifted to the middle chain ring at the front I started slipping violently out of gear. I thought at first that the derailleur had been knocked out of alignment, but after getting off and taking a look it seems I have a more serious problem.
It looks as though a couple of teeth on the middle chain ring have either broken, or worn down to about half their original length. As a result if the chain is turning across the tooth at the same time I’m putting a lot of downward force on it, either through climbing a hill or pushing off from a standing start, the chain is leaping off the ring and either ending up on the smallest ring, or entirely off the chain rings.
You can see what I’m talking about here, and apologies in advance for the mess:
Chainring
With worn teeth highlighted
It’s looking like the only cure is to replace the two chain rings, which by the looks of it amounts to a similar cost to buying an entirely new crank set. I’m tempted to buy a whole new set as the chances are that I’ll inexpertly manage to ding up either the new chain rings or the originals during installation and be right back to square one.
I’ve been reading up a bit on wear and tear on bike drive trains and it looks like I’ll need to check the chain and rear cassette as well. Seemingly much of the wear that I’m seeing is usually cause by a worn out chain as much as anything else. It could be that the gears I use the most on the back cassette are as worn, if not more worn out than the front ones. If that’s the case I’d be as well replacing the crank set, chain and cassette in one fell swoop rather than buying them piecemeal and creating more problems for myself further down the line.
In the meantime the bike is out of commission for fear of damaging something else on it.
