Go Back   Horizons Unlimited - The HUBB > Technical, Bike forums > Yamaha Tech
Yamaha XT 600 (start-up smoke) *video* Yamaha XT 600 (start-up smoke) *video*
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 Marc Gibaud, Clouds on Tres Cerros and Mount Fitzroy, Argentinian Patagonia

The only impossible journey
is the one
you never begin

25 years of HU Events


Destination ANYWHERE...
Adventure EVERYWHERE!



Photo by Marc Gibaud,
Clouds on Tres Cerros and
Mount Fitzroy, Argentinian Patagonia



Like Tree23Likes

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 26 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: Feb 2012
Location: Milan, Italy
Posts: 627
most likely dirt in / bad check valve letting the cases fill with oil even after a few hours.
if anything else was suspect, there's no reason the engine would stop smoking after a while.

easy to check:
check your oil level after a long ride.
check again after an overnight, if level dropped considerably, then it's a bad check valve
Reply With Quote
  #2  
Old 27 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: Dec 2008
Location: Denmark
Posts: 1,417
Sidenote to the above... Oil expands when hot. I think in our bike with a good amount of oil, the difference could be 1-2dl in volume from very cold vs very hot. (I think i calculated the difference once, but cant recall the exact number)

Take notice of how much you drain
Reply With Quote
  #3  
Old 27 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: May 2013
Location: Wisconsin, USA
Posts: 827
Smoke on startup but not when normal running is valve seals , oil seeps past and settles on the piston when it's sitting . I polish valve ends to keep from tearing new seals.

The rings are 95% fully seated within the first 15-20min running . I tested one new motor and it reach 90% of its final compression in 5min, then took another 10 minutes to get the rest . After the 30min mark it was done (208psi ). Never, ever, ever, use synthetic or semi synthetic(not as bad), they prevent seating .
Reply With Quote
  #4  
Old 27 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: Sep 2012
Location: Middle USA
Posts: 349
JJ, what is your suggestions for breaking in a newly bored cylinder, new OEM piston and rings? I am a few days away from starting it.
__________________
'84 XT600 is now bored to 2nd oversize and new OEM pistons and rings installed. No more smoking.
Reply With Quote
  #5  
Old 27 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: May 2013
Location: Wisconsin, USA
Posts: 827
I had noted it in another thread (and got bashed for it) , just start it up letting it warm for a minute or 2 but be ready to ride it . take it through the first three gears no more than 2/3 throttle , hold for a bit then release the throttle and let the motor slow the bike down . Do that for the first 10-15 min ( reasonably high rpms, then use the motor to slow down). this forces the rings against the hatch marks in both acceleration and deccel). Change oil & filter . It's now mostly done but I don't run full rpms for 100 miles at least , always varying the throttle and will heat it up good for 10 min then shut down to cool till it's past the 1/2hr run time. No sustained high rpms for 250-500miles.(Change oil ?? or not , what ever a person wants here)

The one I tested throughout break-in for compression had been done in my garage using the rear brake for loading . Shutting down every couple minutes to check compression.
Reply With Quote
  #6  
Old 27 Apr 2016
mollydog's Avatar
R.I.P.
Veteran HUBBer
  
Join Date: Aug 2003
Location: california
Posts: 3,821
The above break in is pretty good but I would add that HEAT CYCLES are also very important in the first 200 miles of operation on a new motor or new parts.

Run bike as described above ... then park it 10 minutes, let cool.
Repeat, Repeat, Repeat ... you're done!

This is how both Honda and Suzuki have done it with 30 new press test bikes at
new model launch. A few heat cycles and straight onto the track where they spent the next two days at redline! No problems.
Reply With Quote
  #7  
Old 28 Apr 2016
Registered Users
HUBB regular
  
Join Date: Apr 2016
Posts: 48
Quote:
Originally Posted by turboguzzi View Post
most likely dirt in / bad check valve letting the cases fill with oil even after a few hours.
if anything else was suspect, there's no reason the engine would stop smoking after a while.

easy to check:
check your oil level after a long ride.
check again after an overnight, if level dropped considerably, then it's a bad check valve
What do you mean with "bad check valve" ?
Reply With Quote
  #8  
Old 28 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: Dec 2008
Location: Denmark
Posts: 1,417
Any info regarding the heat cycles? My bike never got hot after a rebore and new piston...At leats no heat was transferred to the oil to show an oil temperatre above normal...?

Oeh yeah, most new bikes are just about redlined on a dyno before they even leave the factory... So theres the ring seal and and heat cycle for ya
Reply With Quote
  #9  
Old 28 Apr 2016
mollydog's Avatar
R.I.P.
Veteran HUBBer
  
Join Date: Aug 2003
Location: california
Posts: 3,821
Heat cycles just let new parts expand (heat) and contract (cool), allowing parts to scuff each other and speed break in due to expansion and contraction.

I figure if Suzuki, Honda and Triumph use this technique on new bikes then it should be OK for a new bike or newly rebuilt bike. I still follow break in procedures after doing heat cycles, like never running at steady RPM and never lugging the motor. I also like to snap off throttle and coast down. All this is good for a new engine, valve gear, rings, et al.

PS: you are right, OEM's do rev them to test them, check oil pressure. I've even heard they do this with ONLY assembly oil ... crankcase empty of oil.
But I didn't see this myself ... so can't verify.
Reply With Quote
  #10  
Old 29 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: Feb 2012
Location: Milan, Italy
Posts: 627
Quote:
Originally Posted by danimalu View Post
What do you mean with "bad check valve" ?
yo, lets not hijack this thread

study a bit your oil system from the manual. under the right side cover there is a check valve with a steel bal and spring that "should" prevent the tank draining oil to the motr when not working

open the right cover and youll see it
Reply With Quote
  #11  
Old 30 Apr 2016
Registered Users
HUBB regular
  
Join Date: Apr 2016
Posts: 48
Quote:
Originally Posted by turboguzzi View Post
yo, lets not hijack this thread

study a bit your oil system from the manual. under the right side cover there is a check valve with a steel bal and spring that "should" prevent the tank draining oil to the motr when not working

open the right cover and youll see it

Aaa,and how i check if it's ok?
Reply With Quote
  #12  
Old 30 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: Feb 2012
Location: Milan, Italy
Posts: 627
the ball should move freely, no dirt trapped between ball and seat, sealing o-ring might be squashed and old-change it . dismantle it all, good clean in solvent, remount with fresh o-ring, be careful not to let any sealant into the valve. the o-ring doesnt need sealant to seal

but before you jump into this, do the very easy check i proposed you before the thread went into fresh-motor-run-in mode
Reply With Quote
  #13  
Old 30 Apr 2016
Registered Users
HUBB regular
  
Join Date: Apr 2016
Posts: 48
Quote:
Originally Posted by turboguzzi View Post
the ball should move freely, no dirt trapped between ball and seat, sealing o-ring might be squashed and old-change it . dismantle it all, good clean in solvent, remount with fresh o-ring, be careful not to let any sealant into the valve. the o-ring doesnt need sealant to seal

but before you jump into this, do the very easy check i proposed you before the thread went into fresh-motor-run-in mode
Thank you!
Reply With Quote
  #14  
Old 30 Apr 2016
Registered Users
Veteran HUBBer
  
Join Date: May 2013
Location: Wisconsin, USA
Posts: 827
I saw your video on a better screen now . It's your valves seals . The way it took a few seconds after starting to start smoking , got bad , then slowly tapered away , that's the seals . Rings would smoke right away , then get worse as it warms up and have some smoke the entire time it is running . Your's quits after a minute or so right?

Too much oil would simply smoke till the oil is gone or force it out somewhere and drip on the ground . The check valve has nothing to do with it other than making it harder to check oil , even then if the valve was shot the scavenge pump will keep the motor from filling and you check the oil level in the tank as soon as you shut it off rather than waiting a couple minutes.
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

Similar Threads
Thread Thread Starter Forum Replies Last Post
XT600E Service Manual Download kentfallen Yamaha Tech 96 5 Days Ago 08:04
XT600 - Model Codes kentfallen Yamaha Tech 27 3 Aug 2019 16:36
XT600 Parts Manuals (1990 - 2002) kentfallen Yamaha Tech 5 29 Jul 2016 11:13
2015 - Heading east from Europe, add your itinerary / plans kim Travellers Seeking Travellers 190 5 Mar 2016 07:38
TTR 600 hard to start but runs well FS Yamaha Tech 24 10 Aug 2015 13:49

 
 

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

25 years of HU Events
Be sure to join us for this huge milestone!

ALL Dates subject to change.

2025 Confirmed Events:

Virginia: April 24-27
Queensland is back! May 2-5
Germany Summer: May 29-June 1
Ecuador June 13-15
Bulgaria Mini: June 27-29
CanWest: July 10-13
Switzerland: Aug 14-17
Romania: Aug 22-24
Austria: Sept. 11-14
California: September 18-21
France: September 19-21
New York: October 9-12 NEW!
Germany Autumn: Oct 30-Nov 2

2026 Confirmed Dates:
(get your holidays booked!)

Virginia: April 23-26
Queensland: May 1-4
CanWest: July 9-12

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.

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 Rescue Travel Insurance™ combines into a single integrated program the best evacuation and rescue with the premier travel insurance coverages designed for adventurers and travel is covered on motorcycles of all sizes.
(ONLY US RESIDENTS and currently has a limit of 60 days.)

Ripcord Evacuation Insurance is available for ALL nationalities.


 

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!

Every book a diary
Every chapter a day
Every day a journey
Refreshingly honest and compelling tales: the hights and lows of a life on the road. Solo, unsupported, budget journeys of discovery.
Authentic, engaging and evocative travel memoirs, overland, around the world and through life.
All 8 books available from the author or as eBooks and audio books



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 10:42.

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