Go Back   Horizons Unlimited - The HUBB > Technical, Bike forums > Yamaha Tech
Yamaha Tech Originally the Yamaha XT600 Tech Forum, due to demand it now includes all Yamaha's technical / mechanical / repair / preparation questions.
Photo by Daniel Rintz, Himba children, Namibia

The only impossible journey
is the one
you never begin

Photo by Daniel Rintz,
Himba children, Namibia



Reply
 
LinkBack Thread Tools Display Modes
  #16  
Old 4 Jun 2008
Registered Users
HUBB regular
 
Join Date: Aug 2006
Location: n.ireland
Posts: 49
right guys im gonna give these a shot but 1 thing im a bit unsure about is the

4.75 -17 (120/90-17) as the size of my metzler tourance is 130/80/17 also
is the 4.75 reffering to rim width
__________________
2002 xt600e
Reply With Quote
  #17  
Old 4 Jun 2008
kentfallen's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Jan 2008
Location: Bexhill, East Sussex, England, UK
Posts: 673
What bike are you fitting them too?

As I've already said, it is sometimes possible to fit slightly different tyres to bikes. My XT6 has 120/90 17 Rear 90/90 21 Front. I have been informed that it is possible to fit 130/80 17 to the rear wheel. Aparently, the width is used in the height or vice versa... Not quite sure of the science here.

I'm sure someone else (more technically minded) will be able to help you out here... That's what this thing is for after all. It would certainly help if you could tell us what model bike you have.
__________________
Triumph Bonneville 800 (2004), Yamaha XT600E (1999), Honda XBR500 (1986).


Last edited by kentfallen; 4 Jun 2008 at 20:36.
Reply With Quote
  #18  
Old 4 Jun 2008
Registered Users
HUBB regular
 
Join Date: Aug 2006
Location: n.ireland
Posts: 49
oops thought i had it in my sig 2002 xt600e
__________________
2002 xt600e
Reply With Quote
  #19  
Old 4 Jun 2008
kentfallen's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Jan 2008
Location: Bexhill, East Sussex, England, UK
Posts: 673
That helps....

The standard tyre size for a XT600E is -

Front - 90/90 21
Rear - 120/90 17


I presume your bike is completely standard. It sounds like someone has in the past fitted a different tyre size! Perhaps before you had it?

I would try stick to STANDARD sizes if possible. The 130/80 17 you refer to can be fitted according to some odd people. A different (non-standard) size MAY adversely effect handling etc...

The Michelin website actually recommends fitting either tyre size!!!!!!!!!!! - Michelin offers

I opted for the STANDARD size SIRAC's (120/90 17 - 90/90 21).

I believe that Trellesport do manufacture Army Specials to all those sizes.
__________________
Triumph Bonneville 800 (2004), Yamaha XT600E (1999), Honda XBR500 (1986).


Last edited by kentfallen; 4 Jun 2008 at 20:33.
Reply With Quote
  #20  
Old 9 Jun 2008
Registered Users
HUBB regular
 
Join Date: Aug 2006
Location: n.ireland
Posts: 49
well i got the tires today and got em on the bike handy enough.
tell ya what going from a 17" moto wheel with a road tire to a 21"wheel with a nobly on it is so weird hte steering feels so tight at the bars as in to pull left or right requires a tad more effort nothing to silly but noticeable none the less
tire sizes r as kentfallen says 4.75 -17 (120/90-17) the 4.75 had me a tad confused but it be on with no probs

hopfully this weekend ill get a chance to do a bit of offroading at the local leadmines if so ill tell yas how they go

plus once i get my hands on a mobile with a decent cam on it ill get a few pics up for yas (lost my sony k800i on a building site ) does look well with noblys on it
__________________
2002 xt600e
Reply With Quote
  #21  
Old 10 Jun 2008
kentfallen's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Jan 2008
Location: Bexhill, East Sussex, England, UK
Posts: 673
Glad to been of help here. Ride safely...
__________________
Triumph Bonneville 800 (2004), Yamaha XT600E (1999), Honda XBR500 (1986).

Reply With Quote
  #22  
Old 12 Jun 2008
Registered Users
HUBB regular
 
Join Date: Feb 2008
Location: Stoke UK
Posts: 70
Righto, now the technical stuff.

These tyres are dual marked - that is they show you the size of the tyre in 2 ways.

A tyre size is defined by three characteristics, the nominal section width, the aspect ratio and the rim diameter it suits. That's why you see three numbers on a modern tyre size description.

The metric marking is the 120/90- 17 marking. The 120 is the nominal section width in millimetres. (The width of the tyre), the 90 is the aspect ratio, expressed as a percentage of the nominal section width, (the height of the tyre as a percentage of it's width, so in this case 90% of 120 mm = 108mm high), and the 17 is the rim diameter in inches. (Yeah, I know that's not metric, but that's the way it's measured).

The nominal section width is the width of a fitted, unloaded but inflated tyre. Squat behind the bike, and picture the sectional view of that tyre, if you cut sideways, along the plane of the axle. The widest point (not neccesarily the tread, could be the sidewall, and not including any raised lettering etc) is the sectional width.

The aspect ratio is the nominal section width, divided by the nominal height of the tyre, expressed as a percentage. The sectional height is measured again as fitted, inflated, but unladen, and is the measurement from the lowest part of the tyre section (usualy the bead heel, where it sits against the rim) in a straight vertical line to the highest point of the tyre, (usualy the top centre of the tread).

The rim diameter is not the diameter of the hole in the middle of the tyre, but the wheel diameter it should be fitted to, measured at the point that the tyre bead heel sits.

Imperial is the 4.75 - 17 marking. The 4.75 is the nominal section width in inches, (how wide the tyre is), the 17 is the rim diameter in inches. The lack of an aspect ratio figure implies an aspect ratio of 80%. Traditionaly all tyres had an aspect ratio of 80%, so no one bothered to to mention it.

So the definition of a low profile tyre is one with an aspect ratio of less than 80% - good for feedback, handling and stiffness, bad for comfort noise and rim protection.

An awful lot of work is done by the big tyre manufacturers with the vehicle manufacturers to get the right tyre for the requirements of the vehicle. The tyre manufacturers are the people to ask about which tyre to fit. Std size is best 99.99% of the time. Unless it's on it's original tyres, check what they should be with the tyre manufacturers. They may be more than one recommeded size, and they will feel very different on the bike. Michelin have technical helplines (local rate numbers) where real people will tell you what tyre options there are for your bike, and what pressures you should be running in what conditions. I assume the other big manufacturers do the same. The web sites should give you some good advice too.

Hope this helps.
Reply With Quote
  #23  
Old 15 Jun 2008
Registered Users
HUBB regular
 
Join Date: Aug 2006
Location: n.ireland
Posts: 49
well guys i had em of road over the weekend and they performed tops i managed to claber a m8 that was trailing me from head to toe with puty like mud so they get full marks in that section (woodland and rocky terrain )

also as far as onroad use goes u do become used to them they felt odd as fook to start with but a few hours with em and there spot on (wet roads still to happen)

1 thing that did cause a bit of a hickup was the gear stick getting bent back 90 degrees luckily enough it was steel and could be re shaped
__________________
2002 xt600e
Reply With Quote
  #24  
Old 16 Jun 2008
kentfallen's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Jan 2008
Location: Bexhill, East Sussex, England, UK
Posts: 673
Nice to hear that the tyres are performing so well... Keep us informed of any developments. I'm giving serious consideration to fitting a pair when my Michelin Sirac's need replacing...

ENJOY
__________________
Triumph Bonneville 800 (2004), Yamaha XT600E (1999), Honda XBR500 (1986).

Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 Registered Users and/or Members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
KTM Military PeerG KTM Tech 118 16 May 2019 02:28
Military R65 g/s tmentzelo BMW Tech 7 16 Sep 2006 22:24
Military color: how bad is it? mertens_k Equipping the Overland Vehicle 3 26 Apr 2004 18:46
Ex military Harley MT 350 ctc Which Bike? 3 22 Oct 2003 16:37
US military maps of Egypt LandRoverNomad North Africa 1 7 Jan 2003 21:42

 
 

Announcements

Thinking about traveling? Not sure about the whole thing? Watch the HU Achievable Dream Video Trailers and then get ALL the information you need to get inspired and learn how to travel anywhere in the world!

Have YOU ever wondered who has ridden around the world? We did too - and now here's the list of Circumnavigators!
Check it out now
, and add your information if we didn't find you.

Next HU Eventscalendar

HU Event and other updates on the HUBB Forum "Traveller's Advisories" thread.
ALL Dates subject to change.

2024:

Add yourself to the Updates List for each event!

Questions about an event? Ask here

HUBBUK: info

See all event details

 
World's most listened to Adventure Motorbike Show!
Check the RAW segments; Grant, your HU host is on every month!
Episodes below to listen to while you, err, pretend to do something or other...

2020 Edition of Chris Scott's Adventure Motorcycling Handbook.

2020 Edition of Chris Scott's Adventure Motorcycling Handbook.

"Ultimate global guide for red-blooded bikers planning overseas exploration. Covers choice & preparation of best bike, shipping overseas, baggage design, riding techniques, travel health, visas, documentation, safety and useful addresses." Recommended. (Grant)



Ripcord Rescue Travel Insurance.

Ripcord Rescue Travel Insurance™ combines into a single integrated program the best evacuation and rescue with the premier travel insurance coverages designed for adventurers.

Led by special operations veterans, Stanford Medicine affiliated physicians, paramedics and other travel experts, Ripcord is perfect for adventure seekers, climbers, skiers, sports enthusiasts, hunters, international travelers, humanitarian efforts, expeditions and more.

Ripcord travel protection is now available for ALL nationalities, and travel is covered on motorcycles of all sizes!


 

What others say about HU...

"This site is the BIBLE for international bike travelers." Greg, Australia

"Thank you! The web site, The travels, The insight, The inspiration, Everything, just thanks." Colin, UK

"My friend and I are planning a trip from Singapore to England... We found (the HU) site invaluable as an aid to planning and have based a lot of our purchases (bikes, riding gear, etc.) on what we have learned from this site." Phil, Australia

"I for one always had an adventurous spirit, but you and Susan lit the fire for my trip and I'll be forever grateful for what you two do to inspire others to just do it." Brent, USA

"Your website is a mecca of valuable information and the (video) series is informative, entertaining, and inspiring!" Jennifer, Canada

"Your worldwide organisation and events are the Go To places to for all serious touring and aspiring touring bikers." Trevor, South Africa

"This is the answer to all my questions." Haydn, Australia

"Keep going the excellent work you are doing for Horizons Unlimited - I love it!" Thomas, Germany

Lots more comments here!



Five books by Graham Field!

Diaries of a compulsive traveller
by Graham Field
Book, eBook, Audiobook

"A compelling, honest, inspiring and entertaining writing style with a built-in feel-good factor" Get them NOW from the authors' website and Amazon.com, Amazon.ca, Amazon.co.uk.



Back Road Map Books and Backroad GPS Maps for all of Canada - a must have!

New to Horizons Unlimited?

New to motorcycle travelling? New to the HU site? Confused? Too many options? It's really very simple - just 4 easy steps!

Horizons Unlimited was founded in 1997 by Grant and Susan Johnson following their journey around the world on a BMW R80G/S.

Susan and Grant Johnson Read more about Grant & Susan's story

Membership - help keep us going!

Horizons Unlimited is not a big multi-national company, just two people who love motorcycle travel and have grown what started as a hobby in 1997 into a full time job (usually 8-10 hours per day and 7 days a week) and a labour of love. To keep it going and a roof over our heads, we run events all over the world with the help of volunteers; we sell inspirational and informative DVDs; we have a few selected advertisers; and we make a small amount from memberships.

You don't have to be a Member to come to an HU meeting, access the website, or ask questions on the HUBB. What you get for your membership contribution is our sincere gratitude, good karma and knowing that you're helping to keep the motorcycle travel dream alive. Contributing Members and Gold Members do get additional features on the HUBB. Here's a list of all the Member benefits on the HUBB.




All times are GMT +1. The time now is 07:29.