Bicycle Mechanics - How do i find out what size tyres i need
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09-22-10, 03:16 AM
Hi I have a bike with really damaged tyres and i don't know how to find out what size they are. They are very cracked. I might need to replace the tubes as well. I looked all around the sides where it wedges in and can't see a size written on the tyre. Maybe because they are so cracked it wore off?
I googled and found only this picture http://evansclarke.com.au/detail.asp?id=214407&bigpic=0#img
It is a Southern Cross Odessy 3000.
Thanks for any info/advice!
Based on general styling it looks like it'd be built according to the current MTB standard, which means 26" AKA 559 mm wheels.
Any tire with that exact number will mount up in some manner, but you will need to think about width a bit.
Rims look fairly wide, so I wouldn't go stupidly narrow on the tires. Something at 1.5" or above should do the trick. No need to venture too far above 2" though, unless you intend to use it for serious offroading, which honestly it doesn't look particularly suited for anyhow.
If yours is a similar shape, take care not to put too much money into it. If it needs more than tires/tubes, maybe a chain, scrap it and move on.
When you get tubes, consider what type of valve you want. Schrader (the same as you find on car tires) is handy for machine inflation, but a bit more awkward when hand pumping. Presta is good for hand pumping, but you need an adapter to fill up from a compressor. Tubes are bought for the same size as the tires. One size tube will usually cover several sizes of tire (width). If you're between sizes, go for the slightly narrower tube. They're easier to fit w/o damaging them.
09-22-10, 04:13 AM
Oh thanks so much. yes the tyres are quite wide. I am just using this as a road/footpath bike. We have a lot of bike paths in Sydney now so this is an ideal time for me to get back out there. I have chronic illness and ideally would like to convert this with a motor but on the flat i think i can ride. I have had a year of physio and i work out every day now so i am hope i can ride again. I should have explained that that pic is from the net. It is not the actual bike! The bike i have is a little rusty but i think it is just superficial. Brakes seem to be good and everything else :0)
I have a hand pump that someone gave me and i gave that a go today so that is why i think the tubes are no good as well. I grew up around bikes so the pressure didn't seem very good as well as the cracked tyres.
The seat doesn't lock into place and was a racing style which is no good for me so luckily i had found another seat in the street some time ago. It fit into place much better and is wider. I think i will have to get something even wider but i will slowly see how i go.
I know there is a community organisation that gives out tyres and tubes in Sydney for free as the government is trying to encourage people to get back on bikes.
So I will see what i can get :0)
Thanks for the info...much appreciated!:thumb:
.. I am just using this as a road/footpath bike.
For that kind of usage it's probably OK. But if yours is equipped as the one in the pic (even if it's in a better general condition) then "everything" about it screams low end. Nutted axles, caliper brakes that appear to be made out of stamped metal, style of shifters....
..I have chronic illness
I'm sorry to hear that.
..would like to convert this with a motor.. If yours have the same brakes I'd advise against that.
Even if yours have somewhat more reassuring brakes, I'd still be uncertain about the suitability of such a project. Good side is, that low-end tends to mean easily weldable steel, which can be a bonus for someone planning on modifications.
It is not the actual bike! The bike i have is a little rusty but i think it is just superficial. Brakes seem to be good and everything else Gotcha, but see above. Even ignoring the grime and dirt there's reason for suspicion.
I have a hand pump that someone gave me and i gave that a go today so that is why i think the tubes are no good as well. I grew up around bikes so the pressure didn't seem very good as well as the cracked tyres. Cracked tyres should be replaced, no doubt about that. But unless the tubes are leaking at a higher rate than you can inflate them, there's little-to-no reason as to why they should be stopping you from reaching a decent pressure. I'd blame the pump for that, unless you have Presta valves and aren't familiar with how they work.
If you are physically limited you might just not have the strength to do a proper job? Floor pumps are dead easy. Anyone fit enough to consider riding should be able to get the required pressure with one of those. Usually you get a pressure gauge on those too, which is handy.
The seat doesn't lock into place
Well, that has to be addressed obviously.
..and was a racing style which is no good for me so luckily i had found another seat.. It fit into place much better and is wider.
Time for something that occasional /rookie riders often discard as being snobbish and elitist hair-splitting:
More dedicated riders talk about saddles, not seats. That's because the saddle isn't supposed to carry all your weight other than occasionally. Basically you should have three points of support; pedals, saddle and handlebar and distribute your weight between them. The fitter you are, the less weigth will be carried by the saddle.
If you are physically limited you are unlikely ever to become particularly happy on a MTB w/o some serious modifications. A MTB is intended for a riding position which has you leaning quite a bit forward, to have your arms carry a chunk of your body weight. If that is out of your range you need to look for a bike built from scratch for a more upright riding position, e.g. a cruiser. Or you're looking at changing the stem out to one as short as possible, and a backswept bar as well.
... I think i will have to get something even wider
There's no doubt that saddles CAN be too narrow. Best way to get a hunch if this is the case is to sit on something with a bit of give, like a piece of cardboard, then measure the distance between the indentations made by your sit bones and compare this to the width of the saddle.
Apart from that wider usually isn't the same as better.
Anything with a real stubby nose doesn't belong on a bike anyhow, it interferes too much with the range of motion the legs go through when pedalling.
Softer is rarely better either. Your sit bones might not like it, but they can do the job. When switching to a softer saddle your sit bones sink deeper into the surface, which transfers more pressure onto the squishy area inbetween, which really isn't meant for that task at all.
A saddle should be approached like a pair of traditional leather boots. Even if you have the right size there is a period of adaptation before you can really tell if it's going to work out or not.
09-22-10, 06:03 AM
I don't know. It is a better bike than most people can afford around me. I see some pretty rotten bikes ridden in my local area. It is only the people that live at home with their mums/dads or are rich that can afford bikes that are 100's of dollars :0)
Thanks well the physio seems to have improved my mobility. I just hope the energy will come he he.
OK good to know about modifying it.
Well it is a bike i found so it is fine. I think it is better than anything i rode years back :0)
Oh ok maybe it is the pump. It doesn't seem the best. I had to hold it as i put it in place...in the valve. Maybe the valve is not good either i think!
Well might as well get the tubes anyway!
Yeah i think the bike must have been kept somewhere hot for the tyres to be so cracked. To be honest we were so good with bikes growing up that i have never seen such cracked tyres before. New experience.
Yeah i was thinking of a different pump but this all takes time getting everything i need. I actually got that pump when i scored a different bike but time is something i don't have much of. the other bike was frozen with rust and i just don't have time to fix it. The WD40 also made me sick as do all synthetic substances. Anyway someone else is fixing the bike for themselves now :0)
I will think about another pump later. I am in a network called freecycle and they are good at giving stuff away to each other. Might ask for the pump on that network.
Ah ok yeah saddle :0)
Actually got the other saddle on that i had spare. It fits well and locks into place. More cushioning too which is good he he.
Yeah i did have another bike i bought on ebay(e-bike) but i am in a fight to get a refund at the moment. Long story and that is in another post. This is just a try out free bike until i can come up with something else...I am exploring the options :0)
I know what you mean about weight distribution etc. I will see how i go!
OK will consider that advice about the saddle. Will take it one day at a time :0)
09-22-10, 08:37 AM
I second getting new tubes... I recently picked up a nice vintage MTB from thrift store for 15$, I knew I had to replace the tubes/tires but I wanted to sit on it and get a feel for the bike so I risked pumping up the old tubes, and BOOM! one explodes nearly giving me a heart atttack.. I replace that one and I figure maybe the other one is ok for just going down the driveway (me being lazy) but just as I get down the driveway KABLAM! the other rotten tube explodes.That is no joke if you are going down a hill near traffic!
But yea that bike really is quite low end, you can probably do better going to thrift shops, get something that is at least worth restoring.
09-22-10, 08:49 AM
I just found out that the community organisation i was talking about has tyres for me. They understand what i had to say about me being shy about going back as i wasn't well enough to help out there. Too many problems to name! So I have a name of someone to talk to there.
I am in Australia and we don't get good bikes at thrift stores. I am in the biggest city...Sydney. Everyone charges too much for everything at thrift stores (we call them secondhand stores here) here as the presumption is that everyone is rich if they live in a city! So me getting on on the street is the way to go. Anyway this bike is for now as i said. I might get whatever in the future. I can't spend time on restoring...or energy. I just want to get on a bike and see how i go! :0)
11-03-10, 07:59 AM
Good news i got a better bike from a friend and he found it on the street! I have been riding that for 2 weeks now. Will still get an ebike though when i can as i am stuffed trying to go up any hill or down one. It is an easy to ride bike.
I went to that community organisation called Bike Club and they were helpful in replacing the tyres on the bike i first mentioned in this thread so i swapped that bike with my friends bike that i am using now. Bike club also has a yahoo group so if there are any aussies especially Sydney people then look them up. They have the club 5-9pm at Redfern in a Department of Housing carpark. They have tools, parts and lots of people that help each other. The whole thing is you give back and help other people too. They do have fully assembled bikes to give away but they want to know your not going to take a bike and piss off. Ollie is the dude i saw and he gave me heaps of advice. Plus he showed me how to align wheels! I thought i knew bicycles :0)
Oh btw we found out the tubes were fine....how odd is that!
...Oh btw we found out the tubes were fine....how odd is that!
Not that odd at all. The tire has protected them from direct sunlight and the most of the other nasties. Also, the tube has a much easier job, it only has to hold air. The tire has to have some looks to it, has to be reasonably wear resistant, and has to be strong enough to deal with the tension caused by the pressure inside.
11-08-10, 06:14 AM
Yes i am glad! My friend is using the bike i originally posted about and i am using the Huffy bike!
rapattack, Well it looks like things are looking up. :)
With a few miles the uphills will become easier, but I am curious about your downhill remark. Is it a braking problem?
PS If you don't wear a helmet, please consider doing so.
11-08-10, 06:57 AM
Oh no both up and down are bad. I have CFS/M.E and it is amazing to get this far but there is no chance i am riding with leg power on its own up a hill. It took me 1.5years of physio to get to a point to get on a bike after 20 years of illness so nope no hills! Downhill it is because i know i could not handle it. The speed scares the crap out of me. I try to slow myself down and that is not slow enough. My brain will not handle too much input so i need slow. So i can see cars, people, obsticles etc. So the processor can process the information. Plus i don't want to get into an accident :0)
Oh yes a helmet is a must. In Australia everyone must wear one. I get into accidents all the time and i am not on a bike lol. I am thinking of one of those electric tricycles but they are too pricey!
rapattack, Ahh, now I understand. I congratulate you!
11-08-10, 10:27 AM
Oh thanks so much! I am trying so hard to improve my life. I am on a pension so selling things i get that were being thrown out by rich people is funding the electric bike i want to get. Ebay might be a pain for most things but that is how i sell the junk i save from landfill :0) I also am able to buy herbal medicines that really enhance my life! Ah well better get to my workout and get to bed...thanks!!!
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