Not registered? Then you're not seeing all there is to see. Do you want to contribute? Register now by clicking HERE!
 
  Forums  
 
Advertise with us
Advertise with us
 
 All Forums
 Classic, Historic & Post Classic Motorcycling
 Post Classic Forum
 tyre brands
 New Topic  Topic Locked
 Printer Friendly
Author Previous Topic Topic Next Topic  
  Current Topic Rating: Total Rating: 0 | Join the Forum to Rate this Topic at: Classic Motorcycling Australia Forums  

slider84
Level 1 Member

Queensland


17 Posts

Posted - 02 Oct 2009 :  6:11:56 PM  Show Profile Send slider84 a Private Message  

 
i am building a twin yamaha for post classic racing and need to know what brand and model tyres i can use. i want a 90/90 x 18 on the front and 110x 18 on the rear.
whats the hot ticket.
thanks mark

Bummers
Level 3 Member

Queensland


244 Posts

Posted - 02 Oct 2009 :  7:51:53 PM  Show Profile  Visit Bummers's Homepage Send Bummers a Private Message  

 
Bridgestone BT39s are good & cheaper than Avons.
I use a 2.50x18 BT39SS on a 1.6mm rim on the front of my Championship winning 125 (But I'm looking to change to a 1.85 front rim soon.)
And 100/90x18 on a 2.15mm rim on the rear.
Available from JN's Race Tyres in Brisbane.
 

 
“Racing is life. Anything before or after is just waiting.” Steve McQueen
Go to Top of Page

GD66
Senior Member

Western Australia


390 Posts

Posted - 02 Oct 2009 :  10:21:47 PM  Show Profile Send GD66 a Private Message  

 
What size twin, slider ? I am still using a 90/90 front, 100/90 rear set of Dunlop TT900 GPs,(Card-carrying fat bastard on CB350 Honda)... still good value really at $140 a rear, and almost always available. For sticky Dunlops in the KR range, you'd be better advised to fly them in from the UK.
Go to Top of Page

slider84
Level 1 Member

Queensland


17 Posts

Posted - 03 Oct 2009 :  08:26:47 AM  Show Profile Send slider84 a Private Message  

 
yamaha ds7 250 , rephased crank to 90, special programable ignition,porting pipes modified heads and compression at 18 to 1 and good old methanol. should be a screamer just need tyers to handle it. getting to old to be falling down.
Go to Top of Page

GD66
Senior Member

Western Australia


390 Posts

Posted - 03 Oct 2009 :  11:00:03 PM  Show Profile Send GD66 a Private Message  

 
Goodness ! Very interesting project with the 90 deg crank, jampacked with possibilities. Will be following the progress, good luck with your new weapon of choice.
Go to Top of Page

slider84
Level 1 Member

Queensland


17 Posts

Posted - 06 Oct 2009 :  11:07:50 PM  Show Profile Send slider84 a Private Message  

 
yep lots of possibilities. just recieved the ignition today and **** it has some wires
it is going to take a bit of sorting out.it is designed for a rz/banshee so i need to do a bit of machining to make it all fit. also built up the crank today after having it balanced. 300 bucks just in mallory to get the balance factor right, but its good to 12000 and it will last alot longer than 180 deg cranks.by going to 90 you lose 31 % in vibration plus the balancing .i used rz rods bigger and stronger ,had to machine the webs to get them to fit. slowly but surly it is coming together.
Go to Top of Page

CB72
Level 2 Member


39 Posts

Posted - 30 Nov 2009 :  6:18:51 PM  Show Profile  Visit CB72's Homepage Send CB72 a Private Message  

 
Bummers,

Did i understand you to say that you are planning on using BT39 in 100/90? How does that compare in grip to say AVON race tyres or to Dunlop TT900s?

I use AVONs in the US but was horrified when I saw what they cost back in OZ and I need a good set of tyres to protect the rims of my CB72 350 that I plan on resurrecting in the next couple of months when I'm back in Melbourne.
Go to Top of Page

CB72
Level 2 Member


39 Posts

Posted - 30 Nov 2009 :  6:28:32 PM  Show Profile  Visit CB72's Homepage Send CB72 a Private Message  

 
Slider,
Interesting project. You are obviously thinking about things but 18:1 compression seems high.

I ran a CB72 on methanol but never a 2 stroke, but I keep hearing that 2 strokes don't like the compression with methanol that we expect on a 4 stroke.

My TZ's are around 15:1 static CR but the guys I know in OZ that used to race TZs back in the day claim that they reduced compression for methanol.



Go to Top of Page

Bummers
Level 3 Member

Queensland


244 Posts

Posted - 30 Nov 2009 :  10:38:23 PM  Show Profile  Visit Bummers's Homepage Send Bummers a Private Message  

 
CB72,
The BT39s piss all over TT900s. I could never get enough heat into TT900s to get them to hang on. I tried lowering pressures until they walked all over the place.
I've never tried Avons on my 125 but have ridden a mate's RD250 race bike with them. From that somewhat indirect comparison I'd say the tyres were comparable.
I've been using the 100/90 BT39 on the rear of my bike for several years and the 2.50 on the front.
 

 
“Racing is life. Anything before or after is just waiting.” Steve McQueen
Go to Top of Page

CB72
Level 2 Member


39 Posts

Posted - 01 Dec 2009 :  02:12:37 AM  Show Profile  Visit CB72's Homepage Send CB72 a Private Message  

 
Thanks Bummers,

Just to be 100% clear on this are we talking road compounds or the skinny race compound tyres designed for the Honda 50?

Go to Top of Page

Bummers
Level 3 Member

Queensland


244 Posts

Posted - 01 Dec 2009 :  07:57:55 AM  Show Profile  Visit Bummers's Homepage Send Bummers a Private Message  

 

See John Newton's site, that's where I get my tyres:
You must be logged in to see this link.
 

 
“Racing is life. Anything before or after is just waiting.” Steve McQueen
Go to Top of Page

john feakes
Advanced Member

Victoria


791 Posts

Posted - 01 Dec 2009 :  08:16:44 AM  Show Profile Send john feakes a Private Message  

 
My BT39s (2.5x18) say not for highway use.
 

 
125 RIDERS' ALLIANCE

A wise person simplifies the complicated, a fool complicates the simple.
Go to Top of Page

CB72
Level 2 Member


39 Posts

Posted - 01 Dec 2009 :  1:32:52 PM  Show Profile  Visit CB72's Homepage Send CB72 a Private Message  

 
Thanks john. that makes perfect sense. they are lighter construction and are designed to fit the Honda CR110 replica for a race series in japan.

Many CB160 pilots in the US run them at both ends on stock WM1 1.60" rims
Go to Top of Page
  Previous Topic Topic Next Topic  
 New Topic  Topic Locked
 Printer Friendly
Jump To:
Classic Motorcycling Australia Forums © 2000 - 2023 Go To Top Of Page
This page was put together in 0.19 seconds. Snitz Forums 2000


 
 
 
Copyright © 2000 - 2023 by Classic Motorcycling Australia | Web design by: Greening Computer Services