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View Full Version : My craptastical GN250 tyres (aka omg lots of tyre questions)



Blakomen
14th October 2008, 17:26
I've been given good advice over the last year or so to change my rubbish stock tyres - and i figure while I'm planning to replace the front one soon, I might as well absorb some tyre information.

1) I can't find my owner's manual for my GN250 (i know stupid ey) so does anyone know what the pressures should be for front and rear tyres? (keepin in mind I got the China GN, which I can't find anymore on the suzuki nz website)

2) When I replace the front tyre, do I want the pressure at what the manual says, or what's on the new wheel, or some sort of deviant child of both?

3) Where's the cheapest and closest place in the city to buy a foot pump, so I can check my pressures at home? (i hear michelin single barrel is pretty good)

Thanks for taking the time out from studying to help! (haha yeah... studying... :sleep: more like playing spore)

shingo
14th October 2008, 18:05
Can help ya with the best tyre pressure to use, but to check them your best bet is to get a tyre gauge and just use the pump at the nearest garage to pump them up.

Will be cheaper than paying $40 for a single barrel michelin foot pump, and a tyre gauge is a bit more portable.

Squiggles
14th October 2008, 18:27
28f 32r from memory, you can replace them both for better from cycletreads for maybe a tad over 200, banzai should know the exacts.

Agree with Shaun, save your money and just buy a gauge if you want to check them, use the garage pumps

motorbyclist
14th October 2008, 18:50
but beware with garage pumps:

ever since they swapped to the digital ones people have simply been leaving the nozzle in the ground and running over them:slap:

been caught out twice now where the thing was so badly crushed i ended up with significantly less air than what i arrived with:angry2:

so check them first for excessive damage

BANZAI
14th October 2008, 22:11
25psi front and 29psi rear in the manual so I'm following that one.

I use the pump at the shell station in Beach road and it's pretty accurate.
(I got pressure checked at Wild West Honda one time and front was Spot on 25 and rear was slightly low so I guess it's not bad for free pump!)

I'd like to get a pressure gauge but spending stuff on petrol/food/drinks etc :p

If you want to get the tyres done I reccomend Pirelli City demon or Bridgestones or IRC (In this order of preference).

Double check cycletreads before you go in because they say they got the tyre but then when you go in they don't have the product... (They told me they got bridgestone so I was excited to have bridgestones tyres and went into the store but they didn't have it. Instead got Pirelli on front and IRC rear, and so far it's working incredibly well tho. :first:)

Zim_Invader
14th October 2008, 22:22
25psi front and 29psi rear in the manual so I'm following that one.

I use the pump at the shell station in Beach road and it's pretty accurate.
(I got pressure checked at Wild West Honda one time and front was Spot on 25 and rear was slightly low so I guess it's not bad for free pump!)

I'd like to get a pressure gauge but spending stuff on petrol/food/drinks etc :p

If you want to get the tyres done I reccomend Pirelli City demon or Bridgestones or IRC (In this order of preference).

Double check cycletreads before you go in because they say they got the tyre but then when you go in they don't have the product... (They told me they got bridgestone so I was excited to have bridgestones tyres and went into the store but they didn't have it. Instead got Pirelli on front and IRC rear, and so far it's working incredibly well tho. :first:)

why is it that everytime i see the smileys in one of yui's posts i actually imagine his face doing the same expression! why does it just fit the image so well? haha.. i think it deserves a bling!

Blakomen
14th October 2008, 22:36
Thanks guys :D Helpful as always!

motorbyclist
14th October 2008, 22:40
Double check cycletreads before you go in because they say they got the tyre but then when you go in they don't have the product...

had a similar story with a mate's scooter - they had taken the wheel off and everything then found they didn't have the right size tyre:slap:

howdamnhard
14th October 2008, 23:01
28psi front, 32psi rear.

BANZAI
15th October 2008, 06:46
28psi front, 32psi rear.

Where did you guys got that numbers from???

In page 50 of my owner's manual, it says

Solo Riding
Front 175 kPa, 1.75 kgf/cm2, 25psi

Rear 200 kPa, 2.00 kgf/cm2, 29psi

Dual Riding

Front 175 kPa, 1.75 kgf/cm2, 25psi

Rear 225 kPa, 2.25 kgf/cm2, 33psi

Slyer
15th October 2008, 07:36
why is it that everytime i see the smileys in one of yui's posts i actually imagine his face doing the same expression! why does it just fit the image so well? haha.. i think it deserves a bling!
You're such a bling slut zim. :p

Real_Wolf
15th October 2008, 08:19
Banzai, thats for the standard tyres, remember if you change em it will change.

In general, the main thing to remember is the back one should be higher than the front

Badjelly
15th October 2008, 09:11
A manual pump is a handy thing to have around. The tubed tyres on my Scorpio lose pressure pretty quickly and I often find it easier to pump them up at home than to go to a garage.

You should be able to buy a pump for bugger all at the Warehouse, Super Cheap Auto or a bicycle shop. I prefer the traditional type with a handle on the top, fold-out foot thingies on the bottom. A plain old bicycle pump will do the job too. Motorbike tyres are bigger than bicycle tyres, but they run at lower pressure, so pumping them up by hand is not a big deal.

motorbyclist
15th October 2008, 11:00
i just use a car/bike battery operated electric pump..
dunno how much it cost though, but doubt it was much

BANZAI
15th October 2008, 11:16
Banzai, thats for the standard tyres, remember if you change em it will change.

In general, the main thing to remember is the back one should be higher than the front

Hmm that means I gotta check with Cycletreads the proper pressure for my current tyre...

Thanks for the info :)

Real_Wolf
15th October 2008, 19:50
yah, if you have your bike there, and a phone, you can normally just give them a call, and tell them what your tyres are, and your bike.

Or alternatively, its often written on the tyres the maximum pressure.

I know for my one, when my mate who knows stuff bout bikes gave em a call, i got 35 front, 38 back

Squiggles
15th October 2008, 22:29
Or alternatively, its often written on the tyres the maximum pressure.

Ignore what the walls say, they usually state the maximum pressure the tyre can handle, not what the bike should run, to obtain these look in the handbook/manual/justfuckinggoogleit

Question is, do the cast gn rims run tubes or not... of course all mine do (being wire wheels)

I called 28 32 off the top of my head, might've been in my manual, at any rate it handles fine on those

BANZAI
15th October 2008, 22:40
Ignore what the walls say, they usually state the maximum pressure the tyre can handle, not what the bike should run, to obtain these look in the handbook/manual/justfuckinggoogleit

Question is, do the cast gn rims run tubes or not... of course all mine do (being wire wheels)

I called 28 32 off the top of my head, might've been in my manual, at any rate it handles fine on those

So does that mean 25 29(from the book) is ok???? Or I have to call guys at Cycletreads to check? It's cast rim...

Blakomen
15th October 2008, 23:16
Ignore what the walls say, they usually state the maximum pressure the tyre can handle, not what the bike should run, to obtain these look in the handbook/manual/justfuckinggoogleit


I did try - http://www.google.co.nz/search?hl=en&q=gn250+tyre+pressure&btnG=Google+Search&meta=

Apparently google now thinks this is the most relevant thread :D

Squiggles
15th October 2008, 23:23
So does that mean 25 29(from the book) is ok???? Or I have to call guys at Cycletreads to check? It's cast rim...

I dont know, i have spoked rims :laugh:

I tend to use stock pressures, and make slight deviations from them to find what i like, so starting on 25 29, then maybe increasing slightly to see how it feels, returning if im not liking it. More often than not the guys at cycletreads will just chuck you a figure of what they think it should roughly be (typical would be 28 32 for many), and will work at, its not a scientifically proven figure, just one that'll keep you from having flat tyres :eek:

It should also be noted that Fronts are not necessarily less than Rears, the tl is recommended stock 36 36. Others may be higher on the front :Punk:

Ragingrob
15th October 2008, 23:27
I ran 28 32 when I had my GN and it was a LOT better than anything lower.

BANZAI
16th October 2008, 07:02
I'm gonna ask you guys a n00by tyre questions as well then :p

So, if I change the tyre pressure, would "I" be able to feel the difference?
What sort of difference am I looking for? And what is suppose to be the good tyre pressure?(Like if the handling is better in this way, it should be the right etc)

To do tyre pressure setting it's best to take bike out to open road and ride for about 5mins then check the tyre pressure. Also check the warmth of tyre and if it's too hot, pressure is too high, if it's too cold pressure is too low isn't it?

Btw I think rear got tube and front is not.

Ragingrob
16th October 2008, 07:29
I'm gonna ask you guys a n00by tyre questions as well then :p

So, if I change the tyre pressure, would "I" be able to feel the difference?
What sort of difference am I looking for? And what is suppose to be the good tyre pressure?(Like if the handling is better in this way, it should be the right etc)

To do tyre pressure setting it's best to take bike out to open road and ride for about 5mins then check the tyre pressure. Also check the warmth of tyre and if it's too hot, pressure is too high, if it's too cold pressure is too low isn't it?

Btw I think rear got tube and front is not.

You should check your tyre pressures when they are cold as gas expands when it heats up. I think the specified pressures for tyres are for when they're cold.

From my experience you definitely notice a change in tyre pressure. Even by adjusted the pressures by 1psi I ride away with the bike feeling completely different. If you're running on those low pressures now, pump them to 28-32 and I bet you'll ride away saying "shit this is niiice and I'm going way faster!!!".

:rockon:

Squiggles
16th October 2008, 07:48
Slow and sluggish turning for one, excessive flex when cornering, and bottoming out when curbing... It will also accelerate wear


It is important to always inflate the tyre to the correct pressure. Be sure to check cold inflation pressure frequently (i.e. once a week). Although most motorcyclists love to work on their bikes, they seldom remember to check tyre pressures. Correct tyre pressure, however, is critical for safe handling. Over-inflation or extreme tyre pressure will impair your riding comfort and decrease the contact of the tyre with the road. Under-inflation or too little air pressure will result in poor handling and the bike will be inclined to "wander." Improper and insufficient tyre pressure will also cause rapid tyre wear, an increase in fuel consumption, lower top speed, and provide less control. Remember to check the inflation pressure of your tyres weekly.

You will find the correct pressure in the operating manual of the motorcycle. The manufacturer's information is the minimum values only. With luggage or with a second rider the rear tyre needs an extra 0.2 bar, and for high speed riding the pressure of the front tyre should also be increased by 0.2 bar.
Attention: When the recommended pressure has been changed for use off-road (race track, off-road), it must be reset to the correct value before riding on the street.

Of course some run lower for a reason (e.g. racers)

BANZAI
16th October 2008, 07:56
You should check your tyre pressures when they are cold as gas expands when it heats up. I think the specified pressures for tyres are for when they're cold.
:rockon:

Yea, what I'm saying is gtg for ride and see if the tyres too hot or too cold to check if it's the right pressure for you and your tyre.

I think I heard that in Wednesday practice night at Albany.



Slow and sluggish turning for one, excessive flex when cornering, and bottoming out when curbing... It will also accelerate wear

of course some run lower for a reason (e.g. racers)

Thanks for the info!

motorbyclist
16th October 2008, 10:32
low pressure means you waste power flexing rubber, handling suffers, BUT tyres warm up faster and have moar contact area with road (which means lots of wear too)

high pressure gives rigid tyres with lower rolling resistance, sharper handling, BUT you get less contact area, tyres are harder to warm, and things are a bit more 'skittish' if they're pumped right up and you encounter a less than ideal surface. i find on my sprotsbike i get alot more foad feel back too (ie, can feel every little stone/vibration going up through the forks)


for dirtbikes, hard tyre for hard ground and soft tyre for soft ground. easy :D

Blakomen
16th October 2008, 15:01
From my experience you definitely notice a change in tyre pressure.

Yeah totally, mine were pretty low ;_; and after i fixed it up, felt much more solid and secure on the road :done:

BANZAI
20th October 2008, 06:58
:gob: 28 32 is the way to go! It does make huge difference :first: :2thumbsup

Blings awarded. :D

EJK
20th October 2008, 11:02
:gob: 28 32 is the way to go! It does make huge difference :first: :2thumbsup

Blings awarded. :D

And burnout that rear and get the matching CITY DEMON too!! :chase:

BANZAI
20th October 2008, 17:12
And burnout that rear and get the matching CITY DEMON too!! :chase:

Can you pay me for new sets? I'll do Stoppie/Burnout/Wheelie/drift to waste my tyre :p

bosslady
10th March 2013, 13:25
:gob: 28 32 is the way to go! It does make huge difference :first: :2thumbsup

Blings awarded. :D

Interesting, I've been running 24/28 I might try 28/32 next time I go out

Krayy
11th March 2013, 09:14
Keep in mind that most tyre manufacturers will have recommended pressures for a specific tyre. i.e. a lot of new sports tyres can roll with high pressure as the tread dictates the temperature rather than the pressure and flex. It alos depends on gross weight, so more pressure for a heavier load is okay.

Also, when you adjust the pressure and are trying to decide if its right or wrong, try to use your own tyre pressure gauge and carry it with you so that when you increase/decrease you're using the same scale. Some garage air pumps are +- 1 or 2 psi.