Go Back   Horizons Unlimited - The HUBB > Technical, Bike forums > Yamaha Tech
flat spot flat spot
Register FAQ Calendar Today's Posts
Yamaha Tech Originally the Yamaha XT600 Tech Forum, due to demand it now includes all Yamaha's technical / mechanical / repair / preparation questions.
Photo by Alessio Corradini, on the Salar de Uyuni, Bolivia, of two locals

I haven't been everywhere...
but it's on my list!


Photo by Alessio Corradini,
on the Salar de Uyuni, Bolivia,
of two locals



Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 1 Sep 2005
Registered Users
HUBB regular
  
Join Date: Apr 2004
Location: bristol uk
Posts: 67
flat spot
I took my bike for its first long weekend away post running in. I seem to have a flat spot in the accelleration, in 4th and 5th at around 100kph. It doesn't do it every time, and tends to do it more when really pulling such as on a hill. I'm 99% certain that the clutch isn't slipping. The baffles on the exhaust are rattling, and I'm going to take them out. Could the two be connected?
Other than that 500 plus sunny trouble free miles around the south of England. Just what the doctor ordered.
Reply With Quote
  #2  
Old 1 Sep 2005
Registered Users
Veteran HUBBer
  
Join Date: Aug 2002
Location: Hendrik Ido Ambacht, Holland
Posts: 360
BigBrummer, it seems like you have a carb setting job to do. First make sure your air flter is clean and you don't get false air in somewhere [rubbers between carb and head?]. The exhaust wil not cause problems like that. The only important thing is volume. If you have the standard can, no sweat. You can try to improve breathing out a bit with a drill or a saw.
Matt : synthetic oil is not good for our antique engines. Try mineral oil that is specifically for motorbikes. People say that car oil will do, but since you already seem to have a clutch problem, don't try.
p.s. we have the international Ténéré meeting in Holland coming weekend. Drop by and we will diagnose all your problems.

------------------
Fred, XTZ660, Holland.
__________________
Fred, XTZ660, Holland.
Reply With Quote
  #3  
Old 1 Sep 2005
Registered Users
Veteran HUBBer
  
Join Date: Feb 2004
Location: Toulouse, France
Posts: 216
Hi Fred,

Yes I use synthetic oil, because this way I keep it longer than mineral, 8000 kms instead of 6000 kms.
Synthetic is also appropriate in warm weather as summertime..
There is a risk of cluth slip but I only experienced this once when clutch had 80000kms and worn.
I think my "clutch slip" alike problem is solved.
I found a broken link on my chain, making chain slap excessively against swingarm.
The link was bend, probably because something as stone or other got trapped between pinion and link.
It was still useable, though, it would have ended up with chain going off again.

Thanks for the invitatation, I´ll try come service my bike and meet with the dutch tenerists one day, would be fun.

Cheers

Matt
Reply With Quote
  #4  
Old 2 Sep 2005
Registered Users
HUBB regular
  
Join Date: Apr 2004
Location: bristol uk
Posts: 67
Thanks Fred
When you say carb setting, do you mean changing jets, or are there screws which will adjust the mix?
If its any help, I've now noticed that the problem seems to exist if I accellerate quickly at that speed, rather than smoothly through the revs.
Best Dave
Reply With Quote
  #5  
Old 2 Sep 2005
Registered Users
Veteran HUBBer
  
Join Date: Jan 2001
Location: Stockholm
Posts: 651
carb adjustements:
1. Idle mixture. This is not the issue here. Small screw just in front of bowl, difficult to get to. They first engineered the thing w/o starter motor and then put the starter on.
2. Jets. They only determine mixture at full throttle. Unlikely cause.
3. Float level. Unlikely cause if engine running well for the rest.
4. Needle positions. At first thought would think your problem might be solved by lifting needle second carb (right hand) one or more notches making mixture richer during acaccelaration.

Auke
__________________
Auke
http://aukemarieke.blogspot.com
Reply With Quote
  #6  
Old 3 Sep 2005
Registered Users
HUBB regular
  
Join Date: Apr 2004
Location: bristol uk
Posts: 67
Well, my 1% of uncertainty regarding the clutch proved right. My flat spot is indeed a very slight clutch slip at around 4k revs. I assume the plates are slightly worn. Will have to have a look and see.
Dave
Reply With Quote
Reply

« Previous Thread | Next Thread »

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

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

 
 

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

ALL Dates subject to change.

2025 Confirmed Events:

  • Virginia: April 24-27 2025
  • Queensland is back! May 2-4 2025
  • Germany Summer: May 29-June 1 2025
  • CanWest: July 10-13 2025
  • Switzerland: Date TBC
  • Ecuador: Date TBC
  • Romania: Date TBC
  • Austria: Sept. 11-15
  • California: September 18-21
  • France: September 19-21 2025
  • Germany Autumn: Oct 30-Nov 2 2025

Add yourself to the Updates List for each event!

Questions about an event? Ask here

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...

Adventurous Bikers – We've got all your Hygiene & Protection needs SORTED! Powdered Hair & Body Wash, Moisturising Cream Insect Repellent, and Moisturising Cream Sunscreen SPF50. ESSENTIAL | CONVENIENT | FUNCTIONAL.

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!

Your ad could be here, on EVERY page of the HUBB, or the whole website, or as many as you like!

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 12:31.

Contact Us - Horizons Unlimited Motorcycle Travellers Website - Archive - Privacy Statement - Top