engine exhaust smoke

Posted: Thu Sep 28, 2017 4:13 pm

I've been told for a few years that my bike emits a puff of oil smoke when I decelerate/downshift.
My bike now has just over 50K miles on it. I think the PO said the top end was done around 19K miles.
I positioned my video camera onto the right side passenger peg pointing back over the exhaust, a V&H megaphone.
I also noticed what appeared to be some darker smoke on heavier acceleration. Possibly incomplete combustion?
I'm probably very close to getting a major engine rebuild, but not this winter.

https://youtu.be/WDcfRbbl8us

Any input is appreciated.

Chris

Posted: Thu Sep 28, 2017 10:18 pm

Its toast chris...ill do u a favor and take if off your hands Laughing

...all kidding aside...mine puffs black smoke when i let her rip....smokes a bit of blue on choke....your bike is normal..don't forget its not a new bike.

Posted: Thu Sep 28, 2017 11:02 pm

You have a nice riding style Chris. Enjoyed the video! I could see a little smoke on a couple downshifts and at your higher RPM. Bike sounds really good.

Posted: Fri Sep 29, 2017 12:33 am

I didn't see near enough smoke to be concerned.
According to your buddy does it lessen after completely warming up?
Have you noticed a drop in your oil levels?

Bike sounds good, Chris.

Posted: Fri Sep 29, 2017 12:37 am

I would guess it just needs new valve seals

Worth trying anyway. Could save you some bucks!

Posted: Fri Sep 29, 2017 12:44 am

smurdoch wrote:

I didn't see near enough smoke to be concerned.
According to your buddy does it lessen after completely warming up?
Have you noticed a drop in your oil levels?

Bike sounds good, Chris.

Thanks for your input guys. The small puffs of oil smoke on downshifting has been there for a few seasons. The bike does consume oil, but not too much. On the last NE Fall Ride, i added about half a litre over the 3 days of riding.
This engine still runs strong, and runs up to redline in the first 4 gears without a hiccup. I've never tried to pull 9500 RPM in 5th.

Cheers!
Chris

Posted: Fri Sep 29, 2017 12:48 am

Hondo57 wrote:

You have a nice riding style Chris. Enjoyed the video! I could see a little smoke on a couple downshifts and at your higher RPM. Bike sounds really good.

.
Thanks Greg. I had that video camera mounted to my helmet on the NE Fall Ride. The videos are posted on the ride thread. It was the first time I had used this camera. I would like to find a way to eliminate the wind noise.

Cheers!
Chris

Posted: Fri Sep 29, 2017 12:58 am

F-crazy wrote:

I would guess it just needs new valve seals

Worth trying anyway. Could save you some bucks!

Chris, you can put in new valve guide oil seals without taking the motor out of the frame. I did both my 900 and my R that way.

Posted: Fri Sep 29, 2017 1:07 am

swiftnick wrote:

F-crazy wrote:

I would guess it just needs new valve seals

Worth trying anyway. Could save you some bucks!

Chris, you can put in new valve guide oil seals without taking the motor out of the frame. I did both my 900 and my R that way.

I have a set of the valve seals I purchased from Jebby. I'll get them installed before next spring. That should help.
This is my 10th season on this bike and I've put 55K kms on the clock.

Posted: Fri Sep 29, 2017 1:13 am

I checked out the two videos after the first one. I'll have to come for a ride someday and meet all of you. Btw.. I have had my 900 to redline in 5th quite a few times and it is a real rush!! Still had more power but that was fast enough LOL

Posted: Fri Sep 29, 2017 1:52 am

Chris, the brief ride that I took on it told me that your engine is still very strong - I was impressed. I wouldn't worry about it until it gets a lot worse.

Posted: Fri Sep 29, 2017 9:18 am

Hondo57 wrote:

I checked out the two videos after the first one. I'll have to come for a ride someday and meet all of you. Btw.. I have had my 900 to redline in 5th quite a few times and it is a real rush!! Still had more power but that was fast enough LOL

The NE rides are a blast, both on the road and the parking lot parties afterward. You never know what might happen!!
The spring ride is already set, it's always the weekend after Memorial Day (I say the 'weekend' but some of us have been travelling to the location on Wed. to get 3 days of riding in) and the location is West Dover, Vermont.
We rode this location in the spring of 2016. See if you can travel with another Michigan F'r. to split travel costs.

Cheers!
Chris

Posted: Fri Sep 29, 2017 1:03 pm

I'very found a way to tell if your motor has a oil consumption problem.
If you have a garage or can find a place that's completely dark at night, then get the engine temperature up then with it dark as possible shine a bright flashlight at the exhaust while standing behind the bike.
You will see oil smoke that's not visible in the daylight.
I hope this is helpful to you.

Posted: Fri Sep 29, 2017 1:30 pm

That sounds logical, I'll give it a try.

Cheers!
Chris

Posted: Fri Sep 29, 2017 5:10 pm

Again, i wouldn't be overly concerned about 1/2 litre consumption after 3 days.
Especially at the pace of you Hooligans on the videos. haha.

Posted: Fri Sep 29, 2017 5:42 pm

smurdoch wrote:

Again, i wouldn't be overly concerned about 1/2 litre consumption after 3 days.
Especially at the pace of you Hooligans on the videos. haha.

You too should come out to the spring ride Steve, then you could see how we are the speed limit observing, tea drinking gentlemen members of this forum... Wink

Posted: Fri Sep 29, 2017 7:14 pm

I've never noticed your bike smoking from the front of the pack Razz

Posted: Wed Oct 04, 2017 9:59 am

Chris, The valve seals have most likely hardened from the engine heat cycles and age. Once they become brittle and some oil gets past them. When you close the throttle and coast down it causes a high vacuum from the back of the throttle plates to the combustion chamber. The vacuum then pulls some oil down the valve stems and into the intake (and exhaust) ports. A slight amount also comes up the cylinders past the rings but the symptom of worn rings (usually) is constant smoke under acceleration. If you really want to know if it's valve seals borrow a bore scope from a mechanic you know and pull the carbs then look at the intake valves. If they are covered with gloppy & wet carbon / oil then the valve seals are leaking.

Do not sweat it this causes no ill effects until it becomes excessive.

Posted: Wed Oct 04, 2017 10:50 am

Thanks for your input Doc, I will probably do the valve seals (not ME, but my shop who know what they are doing) over the winter. My bike is stored at this shop for the winter.
When it comes down to a major rebuild, I'll probably get you to do the job if you'll take it on.

Take Care,
Chris

Posted: Sat Oct 07, 2017 3:15 pm

TomK's motor led me to two epiphany moments,

1. Use new valves....especially all the exhausts. At less than $200.00 (US) for the exhausts they are worth it.
2. Use NOS Honda cam chains.... I know a guy.

And of course ... looking towards spring of 2019.

Posted: Sat Oct 07, 2017 11:18 pm

I thought popular opinion was that the OEM cam chains are shite??

Posted: Sat Oct 07, 2017 11:40 pm

The old ones, like from the 80s and 90s were good.