What do the triangles on the sidewall of the tire mean?

[crazydj]

Hi guys!

 

I wanna know what do the triangles on the sidewall of the tire mean? During NS, when i went for the Class 3 Conversion Course, i was told that the triangles point to the part of the tire where when the tire is worn out, a small "bulge" would appear on the tire itself.

 

For my Maxxis Promaxx tire, at each triangle which points to the tire surface, a "bulge" is clearly present and the bulge is flush with the tire surface itself. However, the sides of the tire have plenty of grooves, only the top has about 3mm of depth left. I like to inflate my tires to the max.

 

How do i read these triangles? Thanks!

Edited April 1, 2010 by crazydj

[Orleng]

from the triangles, they point across the tire. in the treads, you should notice a small little bump. INSIDE the treads. once your tire wears down to those little bumps, it is time to replace them.

 

look at thread wear indicators

 

http://www.verati.net/care.php

 

http://www.michelin.co.uk/michelinuk/en/car-4x4-van/tyres-worn/20070118153827.html

 

and here's pretty much everything you need to know about tires. credits to totalmotorcycle.

 

http://www.totalmotorcycle.com/maintenance/tires-tyres.htm

 

page 3 & 4 teaches you how to read all the funny sidewall markings. and page 4 gives a few quick tips on how to care for them tires.

Edited April 1, 2010 by Orleng

[Orleng]

i think legal is 1.6mm. prolly can use if less than that, but beware. have seen a bike with tyre so botak until can see the carcass underneath already. how much do you inflate to anyway>

[crazydj]

Thanks man!

 

I inflate my front to 180 kPa and the back to 280kPa. Follow the manual.

[Orleng]

nps, alota useful tips in that page. and also how to use a tire-patch worm tool properly!

 

power, recommended pressures are good. thought when you said maximum, you meant maximum on the sidewall. lol.

[JackOHJack]

nice read, thx.

 

from the triangles, they point across the tire. in the treads, you should notice a small little bump. INSIDE the treads. once your tire wears down to those little bumps, it is time to replace them.

 

look at thread wear indicators

 

http://www.verati.net/care.php

 

http://www.michelin.co.uk/michelinuk/en/car-4x4-van/tyres-worn/20070118153827.html

 

and here's pretty much everything you need to know about tires. credits to totalmotorcycle.

 

http://www.totalmotorcycle.com/maintenance/tires-tyres.htm

 

page 3 & 4 teaches you how to read all the funny sidewall markings. and page 4 gives a few quick tips on how to care for them tires.

[crazydj]

i think 280pka is overkill man..

most 200 front and 230 rear is what i always pump..

 

My manual states:-

Loading condition:

90–198 kg (198–437 lb)

Front:

175 kPa (25 psi) (1.75 kgf/cm²)

Rear:

280 kPa (41 psi) (2.80 kgf/cm²)

 

I used to pump 230kPa, then 250kPa, then 280kPa.

Sluggish to firm.

Bad fuel consumption, best fuel comsumption.

 

EDIT: I just realised and measured my thread. its only 1mm deep! But the ones around have alot. Only the part in contact with the road is only 1mm! Its a Maxxis Promaxx tire by the way.

Edited April 2, 2010 by crazydj

[Orleng]

hhmmm, does the manual state any lower pressure for the rear tire? Cuz afaik, 2 pressures typically, one for solo rider and one for with pillion. Man, 280 does sound a tad high for solo rider. For comparison, my gsr for solo rider is 250. but if it says so in the manual, then it should be correct.

 

yea, it's only natural. the more you inflate, the smaller the contact patch. so, less rolling resistance, which means better f/c, prolly slightly better pick up, but it comes as a price. cuz less contact area, means more force per contact area, which leads to accelerated wear at a certain portion. so, you'll save on fuel, but end up wearing out the centre faster. do take note though, underinflation leads to other problems as well, e.g. overheating of tire due to excessive flexing, which could lead to tire failure. read through the totalmotorcycle pages, should have all the info there.

 

i know there are bikers who'd use their tires until botak. think abt it though, they're the only things keeping you glued to the road. myself, i'd change them. the sides may have plenty of tread left, but it's unlikely your bike spends most of its time travelling on the sides right? to each their own though.

 

edit : it can prolly be ridden on still, 1mm, but do take note that most manufacturers recommend non-usage past the TWI. the grooves in contact will not be able to clear water as well during wet weather, which we're seeing quite a fair bit of nowadays. do take extra care when riding in the wet eh. and for me to be a responsible rider, may i make a responsible suggestion to change them?

[crazydj]

Sian. I wanna change. My mum also ask me to change. Haha.

 

Anyway, i wanna ask about my chain. You know at the wheel sproket, i can move the chain "in and out(3-4mm", "left and right(1-2mm)". Do i need to replace my whole sproket and chain as well? The previous owner, if i am not wrong, he just changed the chain only. It was very long and my mech had to help me cut a few links. No harm changing my whole sporoket and chain as well right? I need to replace my rear brake shoes as well.

[Orleng]

http://www.canyonchasers.net/shop/generic/chain.php

 

some stuff on what to do to a chain and how to look out for stuff.

 

in summary, if you say that a few links have been removed before to tighten the chain up, then it may be that the chain is too worn now. from what you described, 3-4mm in and out. not quite sure what you mean. but, if you pull directly backwards off the rear sprocket and you can expose half the tooth where you pull off the chain, then, yea, time for replacement.

 

never any harm to replace items that are worn out. of course, not excessively like change eo every 500km la. haha. preventive maintenance over costly repairs i say.

 

best is advice from a trusted mech.

 

in the guide above, they mentioned if alu sprockets, change together with chain. also, i think for 2b bikes, chain + sprocket should be quite cheap. just change to stock chain should be good enough, i think almost all nowadays should be o-ring chains already? not enough hp to bother with heavy duty chains n the like.

[crazydj]

I went to take pictures of my bike because knowing myself, i either think there is nothing wrong to save money or i just have that "impulse" to change.

 

Here is my rear tire. As you can see the middle groove is very shallow and the tire has already reached the triangle "bump". Need to replace my tire?

http://i945.photobucket.com/albums/ad291/crazydj_sgbikes/RearTire.jpg?t=1270363939

 

Here is my rear sprocket. Do the teeth look sharp?

http://i945.photobucket.com/albums/ad291/crazydj_sgbikes/RearSprocket.jpg?t=1270364032

 

And here is my chain and sprocket. I pulled out the chain from the sprocket a little. Note that i can also move the chain left and right, up and down as well.

http://i945.photobucket.com/albums/ad291/crazydj_sgbikes/RearSprocketChain.jpg?t=1270364106

 

Do i need to replace my tire and my chain & sprockets?

[kurarensu]

Yes, replace your sprockets and chain (try replacing all together as a set, front & rear sprockets + chain) Should cost ard $50-70.. dont think it's so costly..

 

tyre stil can use for awhile if u're on budget.. but please becareful. stil advised to change thou.. rather u change a lousier brand tyre than risk ur life on this tyre if i were you.. jb also can go n change

[Orleng]

like kurarensu mentioned, rather change to a slightly cheaper but new tyre if you want to save $$. just remember not to corner hard. if wanna corner, get something good. heh. think abt it though, how much more can exp 2b tyre cost vs a set of budget ones? Then average that out to a monthly cost. Not too much right?

 

sprockets-wise, if it don't look like waves, isn't too badly off. though yours, the amt you can pull off it, looks like time for change. lift up chain slack then pull off directly at the rearmost position for better guesstimation.

 

also, left-right lateral play in the chain is normal. Do take note that the chain should be centered on the sprocket tooth, e.g. equal space to the left and right. can see the minute gap when you look directly from behind. if sprocket is rubbing against either inside of the chain, rear wheel may not be in alignment. so the chain is pulling on one side of the sprocket more than the other.

 

as mentioned above again, general wisdom is to change as a set. so the parts can wear in together. personally though, on my older bike, i just change 2 chains to 1 sprocket change. since it's budget steel, and bloody hard as hell. noisier abit, also don't care. though if you mentioned that owner already previously changed only chain, then yea, 2-1, you're due a full set change.