Carrera Crossfire 2 - Chain slipping

[paddyjt]

Hi all

I'm looking for some advice. I recently got the bug for cycling in July last year and decided to get myself what I would call a "beginner" bike (i.e. reasonably inexpensive) and settled on the Carrera Crossfire 2 from Halfords. Seems the perfect match and exceeded my expectations originally.

In September I fell off in a dark tunnel after hitting some mud on the road and damaged the rear derailleur, chain and looked like a few teeth in the cassette were also casualties. I replaced this with what I thought where like for like parts - I changed the cassette, chain and derailleur and everything was well again except I could never really get the gears to shift properly and the cassette wasn't the same as the original (less teeth on the low gear).

A few weeks ago I found the right cassette (with the same number of original teeth on the low gear) and decided to replace it along with a new derailleur (as I suspected the derailleur I installed in September was a bit dodgy and resulting in the poor gear shifts). This solved my shifting issues! I was getting a bit of vibration through the pedals but that eventually went away - suspect it wore away.

I've been enjoying it for the past few weeks but all of a sudden this week when putting load on the crank I noticed that my chain was slipping occasionally (in the middle crank ring). Today I decided to buy a chain wear tool from Halfords. It's got a .75% and 1% wear indicator and to my surprise both ends fit flat on the chain indicating it needed replaces. This surprised me as the bike all in has only done 2,060 miles and the current chain would have covered probably ~1,600 miles.

So back to Halfords, new 8 speed chain by Clarks with a quick link, off with the old and on with the new - didn't need to shorten it as it was actually a bit smaller than the one being replaced (which I had shortened in September to be the size of the original). Checked with the wear indicator again and neither end sits flat on the chain - so I thought my problems will be solved. Nope.... it's now worse than ever! I can get it to slip by just putting a bit of a stomp on the pedal when stationary.

So... after some reading online, and the fact it mostly just slips in the middle crank ring I think the middle crank ring needs replaced (I think it's a unit and all 3 need replaced).

Can someone confirm if this is likely the culprit before I start farting around with the crank? In the last few weeks it's had a new rear cassette, new derailleur and now chain so surely it's the culprit.

Another thing I notices is that Halfords don't appear to sell like for like replacement parts for their own bikes, has anyone else experienced this?

(I know I need's a good clean)

[fausto99]

Yup that middle chainring looks pointy and worn out. I guess you must be a big powerful pedal pusher rather than a spinner

Halfords are not the best for choice of components.

The next step depends on how much sourcing and fitting you want to do yourself.

[TrevA]

Yes, your middle chainring is very worn. When the teeth start to look like a shark’s fin, then it’s going to slip. It looks as though the chainset is riveted, so you won’t be able replace the rings either, so you are looking at a new chainset, but it’s probably cheaper than replacing the chainrings anyway.

Spa Cycles (Google them) sell a range of triple chainsets that may be a suitable replacement. The more you pay, the more durable the chainrings will be.The rings on cheap chainsets are made from either steel or a softer alloy, so they do tend to wear out quickly, though I would expect them to last longer than yours. A worn chain will also prematurely wear the chain rings, so it’s worth keeping an eye on chain wear and change the chain before it gets too worn.

[ElCani]

Nothing particularly to add other than say you’ve done very well to do that to a steel chainring in 2000 miles.

[gregoryoftours]

I can't see the photo but the lifespan of components can be drastically shortened by not cleaning your bike in between rides, especially just oiling the chain without de-gritting it and the other drivetrain parts.

[Chris56]

According to the specification of the Crossfire 2 on the Halfords website, it comes with a Prowheel chainset, something like this:

https://www.ebay.co.uk/itm/PROWHEEL-Tri ... 890.l49292

I've actially got the same one on my MTB - quite cheap but you could upgrade to something like this:

https://www.ebay.co.uk/itm/Shimano-Altu ... 890.l49292

Should be a straight swap but you will need a cranset puller to remove the old one.

[paddyjt]

Thanks everyone for your replies - and for the links Chris56.

I am a complete novice particularly when it comes to repairs but I do like to get my hands dirty - it's the easiest way to learn in my opinion so I'll be having a go and will buy the tools if I don't already have them (I got a bike tool set a few months back). I'll have a look at the upgrade - worth it if I get a few more miles out of it .

fausto99 - I realised last week that I go 100% all the time haha. I don't seem to be able to 'cruise', I'm just constantly putting out as much as I can (which isn't much to be fair) then realise, pull back to enjoy it a bit more and within a few more seconds I'm doing full pelt again!

Cheers all

Edit: And re the bike cleaning! I hold my hands up - and as you can tell from the picture I'm not great at cleaning it as often as I should but I'll try and do better. Worst part about living in a flat is having to get buckets etc downstairs! I told myself I need to get into a better cleaning routine as I'm planning on upgrading in the near future - don't want something more expensive getting into the state the Carrera is in!

[willcee]

Cheap machines have cheap poor steel chainsets when you these days use a bike daily which to all intents is what you bought it for you don't realise that 80 % of bikes are ridden less than 30 miles a year and a stored in damp garages where after a year all the brightwork or steel bolts is now yellow pallor of underdeveloped rust.. ask me how i know, i worked with a guy about 20 years back who made a business supplying bikes to a local university student population, i learned a lot from him , he bought a lot of stuff at Easter when the spring clean of the sheds and garages were being turfed out.. many of the yokes we found languishing in sheds and from bin hokers he knew about he said in his country parlance ''hadnay seen much work of all'' he reckoned ''maybe 20 /30 miles be a guid sonday'' ...in broad scots irish twang..if you want something that lasts forget about 3/4/500 quid bikes..nice paint that' s about it... they are built to a price... coming out of Taiwan at less than 100 each ....the rest is Duty, Transport and PROFIT ...will

[gregoryoftours]

Yes there's no real getting around the cleaning part, everything's so much lighter weight than a car and exposed to the elements that regular cleaning is practically a must if you want stuff to last.

It also helps to use your gears efficiently, using all 3 chainrings and rear sprockets as suitable rather than spinning the small sprockets and mashing the big sprockets all from the middle ring.

The best efficiency and least wearing gears are where the chain line from front to back is relatively straight. One of my friends had the same issue as you, I changed the chain and cassette for the first time on his bike and he'd already worn the middle and big rings to the point of slipping. No cleaning and plenty of mashing in unsuitable gear combinations! If you MTB or ride off road parts wear much, much faster also.

[paddyjt]

Cheers. Really appreciate the feedback. I have more of the 'back story' to give. I haven't been able to use the third crank ring (if that's the correct term) as I appear to have broken the shifter - it doesn't click into the third position. This has been the case for a few months. So - although it appears I favour the middle ring - the fact is I don't actually have access to the third ring and my efforts to source a new shifter have been exhausted - I will have a look on eBay which seems to be the best source of parts for 'cheap' bikes!

I must admit, I've had conversations recently with friends who cycled like me in our youth (talking 90s early 00s) who don't recall ever really having much work done on bikes but feeling like they were used 'ALL THE TIME'.... did dad/mum keep this schedule to themselves or is it a case of we weren't aware of repairs as children or are parts just becoming cheaper and inferior replacements?

[pwu]

If you are looking for a front shifter on ebay look for Deore or SLX, they use glass fibre reinforced plastic rather than resin which I've had crack before. Look to pay about £5+postage.

[gregoryoftours]

One thing you could try would be to thoroughly flush your shifter internals with spray lubricant and work the levers to try and resurrect the clicks. Occasionally shifters stop working because old grease in them hardens/becomes too sticky over time/cold. It might be that your shifter is just damaged but it's worth a try. If you have trouble finding one pm me and I'll send you one for the cost of postage. It would help to post a photo of your current shifter.

I have similar memories of way less maintenance. In part I think that looking back I was riding pretty knackered bikes much of the time, and just forgot that my gears slipped and I had to avoid some of them when pushing hard, or that my brakes hardly worked in the wet etc! Wheels turned but were rough because the hubs had no seals and were worn inside, tyres absolutely knackered etc.

Also as bike components have got less simple over the years there is a tendancy to them wearing faster, and being more finicky. This is an oversimplification but there is some truth to it, eg. the cogs of freewheels and chainrings of old 5 speed non indexed gear systems are so thick that they last much, much longer than more modern stuff that is profiled and thinned to within an inch of its life to provide incredibly slick shifting. Older 'cruder' components are also more forgiving of misaligment/wear/slight knocks etc.