Wide Tyres, Rim Brakes & MTB Mechs | GCN Tech Clinic

Wide Tyres, Rim Brakes & MTB Mechs | GCN Tech Clinic


(Whoosh, Shutter, Click sounds) – Back again for another
episode of the GCN Tech Clinic, where we help solve and answer your bike related technical problems. So, you can get rolling again
as smooth and fast as ever. Let’s crack on, shall we, with
the first question this week. Oh, by the way, if you’ve got
a question leave it down there in the comment section below or, on all forms of social media. First question, this week from
Marek Rosa, “Hi John, love your content on GCN Tech, thank you. I have a Shimano 105, 5800
shifters, 105 cassette and 105 derailleur on my Cross bike. I would like to switch the
derailleur to a Shimano Mountain Bike one for less chain slap. Will the shifters be compatible? Right then. Unfortunately,
it will not be compatible, because Shimano Mountain Bike
levers and Shimano Road Bike levers use different
amounts of lever pull. Now, people out there
will say that it works, etc, etc, but we want perfection,
don’t we, let’s face it. So, there is a solution. It’s a wolf tooth, tanpan connector. What is that? Well, it’s a little roller,
which slots into your rear derailleur, where the cable
would normally go, so the outer cable, and basically,
it has a little wheel on it and that is, going to give
you a different amount of cable pull, so it will work. Uh, I know loads of
people who’ve used them and they seem to be popular
in the sort of gravel scene. So, go ahead and try that, alternatively you could get one of the new
Shimano Altegra RX makes, because that has a clutch built in, so its not going to give you
not as quite much chain slap. Okay, next up is All Hill,
who says that, last weekend they got a puncture by a
long nail and it left a small hole in the Zonda rim
right in the middle of it. Will the small hole decrease
the performance of the wheels? And can All cover or fix with
a kind of glue on the hole? Right, this doesn’t sound like a deal. It sounds to me like the rim is straight. So you’re actually going to
be to be compromised if you’ve put an extra hole in it that’s
not designed to be there because there’s going to
be no sort of reinforcement around it, and it’s not going to be designed in that way what so ever. Personally, and this is my
paranoia totally taking over me, I wouldn’t ever use that
again, because it’s not going to be structurally sound. And I’m pretty sure, the manufacturer is going
to agree with me on that. Uh, now, you have sent any
photos of it so I can’t really assess the damage but it
does sound like its well, a write off sadly. Sorry about that one All. Now we got Scott Bolton with a question. Now Scott has got himself
five and half bikes, the half comes from the
front end of a tandum, but the down side of this is that some do not get ridden
as often as they should. Particularly, the folding commuter. After a few weeks the chain
lube can get a bit thick even if it was put away clean. What is the best way to treat a chain if there’s a chance it will
not get used for a while? Right then, Scott good job there because you’ve put them
away nice and clean, but make sure they’re absolutely gleaming, so you can eat your dinner
off of the top tube. Now don’t go ahead and put
thick lubricant on there, not wet lube or anything like that, because that tends to
attract a lot of dust, instead put a really
light and thin lubricant on there instead. In fact, you could try something like, uh sewing machine oil, I’ve
used that in the past. Because it doesn’t seem to get so sticky and attract everything, it’s
really, really thin and nice. Importantly as well, cover
up the bikes with blankets to stop any of the dust that’s
floating around in the air from landing on that chain. You should be nice and gunk free next time you bring the bike out to play. Now, Neil Partridge is next
up and Neil is just about to buy themselves, their
first ever road bike. Nice one Neil, good decision. But, however, they want to use 28mm tires and the question is, Will caliper breaks always be too narrow and should Neil just look for disc breaks? Or is it not that straightforward,
and every bike different? Right, Neil, good question. Ya, bikes do very hugely,
from one model to another even within brands themselves. So, a few years back, almost
certainly a top end road bike, even mid, even low level
road bikes, entry level, whatever you want to call them. They wouldn’t accommodate
a 28mm wide tire. However, times and trends have changed, people these days use
25s, 28s, past standard. And calipers of brakes
are being redesigned to be able to accommodate them. So, what I would advise is,
speak to the dealer who you’re going to get that bike from and ask them to try and put 28mm tires
onto the different models of bikes that you came to look at. And see which ones fit, that’s
the only way of finding out, I’m afraid, and if they really really, really want that bike sale, they’re going to do it for you, trust me. Next up, is a question from
Tarcis, who has had a real nightmare of a time, by
the sounds of things. For the fourth time,
they’ve had to change their derailluer cable,
because it keeps breaking inside of the shifter about an inch away from where it actually goes in. Now they’ve actually had the
shifter replaced under warranty yet it broke again, they
don’t have sweaty hands. So there is no salt getting
in there to corrode the cable. What could it be? I’m absolutely lost here,
because you’ve had a new shifter in there, initially, I thought
it could well be something jammed inside of the shifter,
that was causing the problem. I was going to suggest
blasting it out with some air or some lubricant, something like that. The only thing I’m thinking is
that you’re trying to change a load of gears at once without pedaling, so, the mech has no where to go, because the chain isn’t moving, so therefore it can’t go up the cassette. If anyone out there could help
Tarcis please do let him know down there in the comment section, because that sounds like
an absolute nightmare. And I’m lost for answers
with that one, for a change. Only thing I can think
of, your outer cables, make sure you put farrells on the end. I can’t think that’s going
to make any difference But yeah, if anyone can
help Tarcis, please do. Now we have a question
from Calliou, who says, “John should I consider
replacing my brake cables as a matter of preventative maintenance?” Is it a good practice to do so? Uh they have the giant TCR
with Shimano 105 brakes for five years now, and a few
thousand kilometers on it. Thanks. Right. Another good cable question. And for the low cost
and also peace of mind, I would be inclined to do it. Cables don’t have a life
span on them per say, it’s not like after so many kilometers they are going to fail and
they should be replaced. Instead, I replace mine,
generally about once a year sometimes more often,
depends on what bike it’s on and also the conditions it’s been used in. It’s better to be safe
than sorry isn’t it. I mean it’s low cost to replace
it, it’s relatively easy to. I would just go ahead and do it. Because after all, you
don’t want them to fail because they’ve been slowly corroding away inside of your bike. Safer than sorry. Penultimate question this
week, is from Mr. Gadangit, who says they’ve had
quite a few tubes recently with holes inside of them
and no apparent culprit. Two were after riding
multiple miles down the road, and the other appeared the
next day with a flat tire. They’ve inspected the rim and
tires closely and carefully with their finger and don’t feel any obvious burs or sharp things. They haven’t hit anything hard
and everything seems normal. Right, I know you’ve had a good check, but check again. This time, really, really closely. And I mean go inside of that tire and rub your finger around
every single bit of surface. Because it’s not uncommon
for a tiny little thorns or bits of wire to get
lodged inside of the tread and just poke through a
fraction of a millimeter. Through the caucus and that
is enough to go through your butyl inner tube, so
have a very, very good look. I’m pretty sure, that’s going
to be the culprit there. As well as actually inside of the rim to make sure there’s no
sharp burs, no rough edges, nothing like that, any bits of spoke hole, anything like that shoving through, because that is enough to
cause a problem there too. I’ve had this happen to me in the past, and yet you will find a very,
very small thing happening. Best thing to do, look
at those old inner tubes that are punctured. And measure the distance
away from the valve, where the hole is. Is it in the same place
each and every time, if so, measure the same
difference on the rim or the tire and look for a foreign
object or a bur there. And the final question this
week comes in from Block Hax who says they have an odd problem whenever they unclip their left foot. For a few seconds, the heel
of the shoe is in contact with the wall of the back tire. It’s an issue that’s wearing at the tire, as well as the shoe, any suggestions? Right then, we actually need
to look at what’s going on here So, when you’re unclipping
from your clipless pedals, you actually want to be twisting your heel outwards away from the bike. For that very reason,
really, you could either damage your shoe, damage the
wheel or worse case scenario actually lock up the back
wheel and you go flying down the road off of the bike. That’s not going to be perfect, is it? So, you always clip
outwards and you’ll be good. Right, I hope that I’ve
managed to answer your question this week in the GCN tech clinic. As ever, if you’ve got
a bike related problem, leave it for me down there in
the comments section below. I am so kean to help answer
them and solve your problems. Please, please, please, I love it. And now, remember as well as the luck you share this video with your friends, and also check out the GCN shop at shop.globalcyclingnetwork.com. And now, for another great video, how about clicking just down here.