the 'there's no such thing as a stupid question' bike maintenance thread

Hi, My brand new gatorskin tyre blew out yesterday after 50km on use. Put in a replacement tube, inflated with compressed CO2 cannister, and it popped about 10 seconds later. At this stage notice the tyre had a 30mm rip between the sidewall and wire. Both tubes has a big hole in almost the same place. Both are the same distance from the valve, the only difference is one is on the rim side and the other on the "road" side.


Any ideas whats causing this?



The wheel seems perfectly "normal" in that location. i.e. no sign of any damage or spokes protruding through the rim tape.



And the reason I have a new tyre is the old tyre went the same way. About a week ago started a ride and only got 1km until blowout. Fixed and cycled another 1km and heard the air coming out pretty quickly, but not quite a blowout.



Called home and got a lift back...when I went to assess the damage the tyre had a rip in exactly the same way the new gatorskin now has a rip.



I dunno - at home I inflate with a track pump to a little below the stated tyre limits, roadside its usually a CO2 cannister.



Really don't know what to do next. It can't be just a string of bad luck????



Any thoughts?

kevin7 wrote: »

Hi, My brand new gatorskin tyre blew out yesterday after 50km on use. Put in a replacement tube, inflated with compressed CO2 cannister, and it popped about 10 seconds later. At this stage notice the tyre had a 30mm rip between the sidewall and wire. Both tubes has a big hole in almost the same place. Both are the same distance from the valve, the only difference is one is on the rim side and the other on the "road" side.


Any ideas whats causing this?



The wheel seems perfectly "normal" in that location. i.e. no sign of any damage or spokes protruding through the rim tape.



And the reason I have a new tyre is the old tyre went the same way. About a week ago started a ride and only got 1km until blowout. Fixed and cycled another 1km and heard the air coming out pretty quickly, but not quite a blowout.



Called home and got a lift back...when I went to assess the damage the tyre had a rip in exactly the same way the new gatorskin now has a rip.



I dunno - at home I inflate with a track pump to a little below the stated tyre limits, roadside its usually a CO2 cannister.



Really don't know what to do next. It can't be just a string of bad luck????



Any thoughts?

If your bike has rim brakes, make sure the pads are not too high. if too high they rub the tyre and will cause a blowout.

Folks this is a pic of tyres of my brand new giant content purchased in feb..went to cyclesuperstore and they said its cosmetic..should i chase for replacement ?

Roberto_gas wrote: »

Folks this is a pic of tyres of my brand new giant content purchased in feb..went to cyclesuperstore and they said its cosmetic..should i chase for replacement ?

They just look like manufacturing marks to me, I'd say they're fine

.red. wrote: »

I didn't want to start a new thread and figured it was (kind of) maintanence related.
I got handed a set of pedals when I bought my bike second hand.
I'm now half thinking of keeping an eye out for a cheap pair of shoes to see how I go with them.
Are these pedals any good for someone who's never used clipless before?

They are similar to the first clipless pedals I used. I didn't get them because they were better for someone who hadn't used them before, but because they are MTB pedals (spd pedals), and I wanted to be able to walk relatively normally in the shoes.

Short answer, they'll be fine to start out in, just make sure you get spd shoes, not spd-sl shoes

Bluejohn1 wrote: »

If I was to buy a new wheelset (Aksium Disc CL 28" Wheel Set) and I wanted to make it as easy/quick as possible to switch between both sets. Is this everything I need to purchase to do so.

- Wheelset
- 105 cassette
- SM-RT30 Center-Lock Disc Rotor x 2
- Centerlock Adapter SM-RTAD05 x 2
- Additional thru axle x 2

I have a cube nuroad race 2019.

I'm open to correction but I don't think you'd need either of the following, since the wheels are already the Centre Lock standard.

- Centerlock Adapter SM-RTAD05 x 2
- Additional thru axle x 2

You don't need the additional thru axles because they stay on the bike - it's not like quick releases where it's very handy to have another set as they stay on the wheels at all times. Some things to be sure of:

Get the same diameter rotors as your current wheel set (usually 160mm for road bikes - but double check).

Check thru axle diameter - almost definitely 12mm road standard on both wheels.

You'll need tyres and tubes if the Mavic wheels don't come with them (sometimes they come as a set).

cletus wrote: »

They just look like manufacturing marks to me, I'd say they're fine

Marks are fine i meant the cracks

Roberto_gas wrote: »

Marks are fine i meant the cracks

You obviously have a better view of the tyres than me, but they don't look like cracks to me, they look like marks left from the manufacturing process.

If you deflate the tyre and put pressure on the tread so as to deform the sidewall, do the marks/cracks become wider? Can you take a picture of them like that?

Cee-Jay-Cee wrote: »

They're the same as the Fulcrum 6, theyre just OE spec wheel for factory bikes.

If they use the same bearings as the Fulcrum 5 (which they probably do as I believe its the 4 and lower that use cup/cone and all above use cartridge bearings) then the bearings in your wheels will be marked 61903 but they're not, they are actually 18307's with 61903's seals. Don't buy ridiculously expensive fulcrum bearings thinking they're proprietary as they're not, just buy 18307's.

Its very simple to change the front wheel bearings. Watch this video.

https://www.youtube.com/watch?v=jsyYlj9cdcM

I walked into a couple of bike shops today, and they looked at me like I had three heads when I asked for 18307 bearings, and after much searching on the internet, one found them, but could take up to a week to get here.
1. is there an easier option, or is this the norm?
2. Would these be useful to have as spares? https://www.aliexpress.com/item/32739268958.html?spm=a2g0s.9042311.0.0.4b404c4dpQg6io

cletus wrote: »

I have disc brakes. I think they are working right. I can pull skids with them. Can you pull skids?

I had the need to do an emergency stop due to a goon in the traffic lane giving way, but the driver never looked to see if anything was in the Bus/cycle lane (me) - the good news is I stopped with a bit of a skid, the bad news is that the levers were almost touching the bars - is that the normal position, or do I need them adjusted?

wheelo01 wrote: »

I walked into a couple of bike shops today, and they looked at me like I had three heads when I asked for 18307 bearings, and after much searching on the internet, one found them, but could take up to a week to get here.
1. is there an easier option, or is this the norm?
2. Would these be useful to have as spares? https://www.aliexpress.com/item/32739268958.html?spm=a2g0s.9042311.0.0.4b404c4dpQg6io

My LBS had them in stock, they referred to them as Trek bearings but they were Enduro bearings.

I have previously bought bearings from BearingKing.co.uk

https://www.bearing-king.co.uk/products.php?search=18307

The only problem with bearings from AliExpress is that you could be waiting anywhere from. 4 to 12 weeks for them to arrive.

Hi All
would anybody be able to advise what kind of replacement BB I would need for this bike?

https://www.cube.eu/en/2017/hardtail/ltd/cube-ltd-pro-2x-blackline-2017/

In the specs it says Pressfit BB, but doesn't mention the model
I have a Shimano Deore XT M8000 Crankset if that helps.

Also would I need a removal tool like this to replace the old one?

Is there a corresponding BB that would fit the above bike/crankset but that can be screwed in rather than press-fit?

Wine corks?

cletus wrote: »

I might have a spare push on plastic set here, if you want them

Ah thanks for that but I wont put you to the trouble, I have 10 generics on the way just wondering about a stopgap, Ill have a look in all the junk drawers at work tomorrow and get something.

wheelo01 wrote: »

Thanks again for your patience.
I have searched a crowd from Tullamore too, they have the 61903 listed, not the other 18307, however they seem reasonably priced in comparison, is there one of these that is more/less suitable?

https://www.bearingsonline.ie/index.php?route=product/search&search=61903#/sort=p.sort_order/order=ASC/limit=50

No they’re all 19mm ID which is too big.

LK bikes in Letterkenny have them for €9 each or get them from bearingKing in the UK. Plenty of them on eBay too.

http://www.lkbikes.com/

Recently went tubeless. LBS cranked the valve lock nuts as they said tire would leak air otherwise even though every video I've seen says to put them on finger tight. Sure enough they were right as I took one lock nut off tonight as they stripped the finish off it tightening it. Fancy lock nuts indeed. As soon as I loosened it a turn or two air starting gushing. Replaced with a nice new one finger tight, pumped back up and air is holding. Will see in morning.

My question is this. If the lock nut is stopping air leaking doesn't that mean there is an issue somewhere else. Perhaps tire not seated correctly around the base of the valve inside the rim or maybe a shoddy rim tape job where they didn't overlap. Or is the lock nut's purpose to seal the rim ? Is this a problem ? New rims so I'd have to get them to inspect and possibly redo the rim tape job if it is.