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.
Contact Overland Solutions for all your custom modifications and setup for overland travel.

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 15 Mar 2004
Registered Users
Veteran HUBBer
 
Join Date: Apr 2002
Location: bizovac, croatia
Posts: 240
1st oversize tolerance ?

Hi,
what tolerance piston/barrel do you recomend for 1st oversize ( 100,5 diameter of piston ) on XTZ 660? According repair manual, minimum is 6/100 mm. Any quality expirience? XTZ 660 is well known oil consumption bike, and i am thinking that making minimum tolerance will decrease consumption?
Regards,
AnteK
__________________
AnteK
Reply With Quote
  #2  
Old 15 Mar 2004
Registered Users
Veteran HUBBer
 
Join Date: Aug 2002
Location: Hendrik Ido Ambacht, Holland
Posts: 360
Hi Ante,
I have 100,5 piston also but have no idea what tolerance the machine shop made for me.
But oil consumption maybe has something to do with the engine not warming up well enough most of the time. This affects a lot of things such as carb mixture, expansion of piston and other parts etc.
I noticed that just after I change oil consumption is always less. So maybe the oil
deteriorates quickly.

------------------
Fred, XTZ660, Holland.
__________________
Fred, XTZ660, Holland.
Reply With Quote
  #3  
Old 15 Mar 2004
Steve Pickford's Avatar
Contributing Member
Veteran HUBBer
 
Join Date: Jul 2003
Location: Oxford, UK
Posts: 1,025
Antek,

Stick to the specified tolerances. If you go smaller, you increase the chances of seizing the engine when it gets hot. The tolerance is there to allow the components to EXPAND under use. Too little tolerance will result in an expanding piston grinding to a halt in a cylinder that is not quite big enough. A trip over the handlebars could be the end result (speaking from experience here!)

Tolerances are specified by the manufacturer & determined by materials & the thermodynamics of that particular engine.

Oil consumption can also be due to worn valve guides, perished valve stem seals, worn rings etc.

When running the new piston in, do not use a a fully synthetic oil. Use a basic oil that meets minimum requirements - this will allow the piston to bed in properly. Once the running in is complete, change the oil & filter, using a higher quality oil. Using a fully synthetic oil when running in will NOT allow the piston to bed in as well.

Steve

__________________
My photos: www.possu.smugmug.com
Reply With Quote
  #4  
Old 17 Mar 2004
Registered Users
Veteran HUBBer
 
Join Date: Aug 2002
Location: Hendrik Ido Ambacht, Holland
Posts: 360
Steve, you must be joking when you talk about the engine getting HOT. It's a 660. We have problems getting it warmed up to normal working temp.
But you're probably right when you say that we should use the factory prescribed tolerances.

------------------
Fred, XTZ660, Holland.
__________________
Fred, XTZ660, Holland.
Reply With Quote
  #5  
Old 17 Mar 2004
Steve Pickford's Avatar
Contributing Member
Veteran HUBBer
 
Join Date: Jul 2003
Location: Oxford, UK
Posts: 1,025
Not had the misfortune to own such a machine......

Leaving the oil out should help the engine get up to temperature....

Steve
__________________
My photos: www.possu.smugmug.com
Reply With Quote
  #6  
Old 17 Mar 2004
Registered Users
Veteran HUBBer
 
Join Date: Aug 2002
Location: Hendrik Ido Ambacht, Holland
Posts: 360
They are perfect in the Sahara when it's 45 degrees and if you really do your best you can even get the oil to rise to 100 degrees.


------------------
Fred, XTZ660, Holland.
__________________
Fred, XTZ660, Holland.
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


 
 


HU DVD Summer Special!

Now that summer is here, get On the Road! Take 30% off the Achievable Dream - On the Road! 2-DVD set until August 31 only. Get On the Road! Learn the tips to staying healthy, happy and secure on your motorcycle adventure!

Our veteran travellers share their tips (and great stories) for staying healthy, happy and secure on your motorcycle adventure.

"A fantastic, informative and inspirational DVD."

"It's brilliant - thank you very much!"

Check it out at the HU Store! Remember to use Coupon Code 'ONTHEROAD' on your order when you checkout.


Renedian Adventures

What others say about HU...

"I just wanted to say thanks for doing this and sharing so much with the rest of us." Dave, USA

"Your website is a mecca of valuable information and the DVD series is informative, entertaining, and inspiring! The new look of the website is very impressive, updated and catchy. Thank you so very much!" Jennifer, Canada

"...Great site. Keep up the good work." Murray and Carmen, Australia

"We just finished a 7 month 22,000+ mile scouting trip from Alaska to the bottom of Chile and I can't tell you how many times we referred to your site for help. From how to adjust your valves, to where to stay in the back country of Peru. Horizons Unlimited was a key player in our success. Motorcycle enthusiasts from around the world are in debt to your services." Alaska Riders

contest pic

10th Annual HU Travellers Photo Contest is on now! This is an opportunity for YOU to show us your best photos and win prizes!

NEW! HU 2014 Adventure Travel T-shirts! are now available in several colors! Be the first kid on your block to have them! New lower prices on synths!

HU 2014 T-shirts now in!

Check out the new Gildan Performance cotton-feel t-shirt - 100% poly, feels like soft cotton!


What turns you on to motorcycle travel?


Global Rescue, WORLDwide evacuation services for EVERYONE

Global Rescue is the premier provider of medical, security and evacuation services worldwide and is the only company that will come to you, wherever you are, and evacuate you to your home hospital of choice. Additionally, Global Rescue places no restrictions on country of citizenship - all nationalities are eligible to sign-up!


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 R80 G/S motorcycle.

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 (22 this year!); 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, the HUBB or to receive the e-zine. 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.


Books & DVDs

amazon

All the best travel books and videos listed and often reviewed on HU's famous Books page. Check it out and get great travel books from all over the world.


Motorcycle Express for shipping and insurance!

Motorcycle Express

MC Air Shipping, (uncrated) USA / Canada / Europe and other areas. Be sure to say "Horizons Unlimited" to get your $25 discount on Shipping!
Insurance - see: For foreigners traveling in US and Canada and for Americans and Canadians traveling in other countries, then mail it to MC Express and get your HU $15 discount!




All times are GMT +1. The time now is 15:05.