Genuine rear tyre size info for a 1981 GS450tx

[s0nia]

Hello, I am yet to get my hands on an original manual for my 1981 GS450tx and am wondering if anyone would be kind enough to share what the rear tyre size is meant to be please? Mine came with a skinny tyre on the back that looks like it should be on the front!

Cheers,
Sonia

[Steve]

Just remember that wider is not always better.

I think it calls for a 110 or 120 width.

Yeah, the front is a 90 or 100.

.

[s0nia]

Thanks Steve. I was just having this exact conversation today. I like wide tyres, but I just really want the genuine sized tyre it would have had on it's rear in 1980 -81.

sonia

[pete]

Hey Sonia, Alpha Sports is your friend

On the parts fiche for the rear wheel for an '81 450TX they list rear tyre size as 110/90-17 and your front is a 90/90-19.

By modern bike standards, they're pretty skinny, but in comparison the modern Suzuki TU250 uses exactly the same tyre sizes as my '82 450E which is a 90/90-18 front and 110/90-18 rear.

If you want to go wider, you may get away with a 120, but I would definitely talk to someone a little more knowledgeable about such things than I...

[Hornswaggle]

There is a factory sticker on my rear fender that confirms what Pete said, 110/90-17

[cowboyup3371]

Have you downloaded the service manual from Basscliff's site yet?

[SVSooke]

Going to wide is not good.Some PO managed to squeeze a 130x18 on my 78 GS1000 rear rim.Bent tire irons trying to get it off.Pretty sure it messed up the handling to.

[Steve]

Hey Sonia, Alpha Sports is your friend

On the parts fiche for the rear wheel for an '81 450TX they list rear tyre size as 110/90-17 and your front is a 90/90-19. ...

Not sure about "down under", but up here, Alpha Sports is a friend only for getting parts numbers.
They tend to charge the highest prices of any of the on-line vendors, usually above MSRP.

As mentioned by others, you can probably go up one size from stock, but beyond that, you will be hurting performance more than you are helping it.

If you have access to a GPS, check your speedo accuracy before getting a front tyre. Many (most?) of our speedos are rather optimistic, so going from a 90/90-19 to a 100/90-19 will slow it down a bit and make it remrkably close.

The larger front tire will slow down the steering feel a bit, but going one size larger on the rear, too, will help neutralize the feel.

.

[pete]

Not sure about "down under", but up here, Alpha Sports is a friend only for getting parts numbers.

Indeed this is very true Steve! I only use that site because their fiche lists all part numbers including discontinued ones.

I buy from Boulevard Suzuki

[s0nia]

Have you downloaded the service manual from Basscliff's site yet?

No I haven't, but in a few seconds I will! I had a quick look the other day trying to follow the "all new user rules" but rushed through it to get to the forum. Thank-you for this diamond of a reminder! Shall go have a look again now.

[s0nia]

There is a factory sticker on my rear fender that confirms what Pete said, 110/90-17

Thank-you, Thank-you, Thank-you.

[s0nia]

Thanks so very much Pete for the parts fiche info and to Steve & SVSooke! I really appreciate all the info and help! Going to stick with the tyre size Pete got from the fiche & Kevin has given me off the sticker on his back fender. Very happy girl here!

Alpha Sports is my friend!

[pete]

Completely forgot! I was going to say get both manuals from BassCliff's site, but just remember there is an odd mistake or two in the Haynes, the Clymer is more reliable.

Also, go spend another $30 or so and buy a reproduction factory manual from here:

http://stores.ebay.com/e-ClassicBike-Manuals?_rdc=1

The one I got from him included all the addendums and things and has been very helpful.

He says if he doesn't have it listed, contact him and he probably will have it available.

[s0nia]

Completely forgot! I was going to say get both manuals from BassCliff's site, but just remember there is an odd mistake or two in the Haynes, the Clymer is more reliable.

Also, go spend another $30 or so and buy a reproduction factory manual from here:

http://stores.ebay.com/e-ClassicBike-Manuals?_rdc=1

The one I got from him included all the addendums and things and has been very helpful.

He says if he doesn't have it listed, contact him and he probably will have it available.

You are such a legend, thanks so much lovely. I just downloaded the clymer, but will go onto ebay and purchase the manual right away.

Thank-you Thank-you

[pete]

Usually my name and legend only appear in the same sentence with a negative in the middle.... haha

But get the Haynes from BassCliff's site as well, it's definitely best to have all three as sometimes you will find an illustration that just doesn't quite help, but one of the other manuals has a perfect one in it.