Strange Exhaust Discovery - Star Motorcycle Forums: Star Raider, V-Max, V-Star, Road-Star Forum
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 14 (permalink) Old 01-15-2015, 02:57 PM Thread Starter
Member
 
Wavelength's Avatar
 
Join Date: Oct 2014
Location: Mims, FL: Home of the Flying Sunset Cans
Posts: 54
Cool Strange Exhaust Discovery

I was getting ready to put the dust cover on after I finished riding and lightly felt the rear exhaust muffler to make sure it wasn't too hot. Just warm, OK. On impulse, I felt the front pipe and was still pretty hot. The next day, I took a ride around the block a couple of times and checked with the temperature sensor. The front pipe near the cylinder was 230 degrees F. The rear pipe same place was 90 degrees F. No, I haven't lost my mind already! The bike is perfectly tuned, adjusted, new synthetic oil, running perfectly, and making no unusual noises. Single carb and the engine and exhaust are stock. Any comments or theories?

2009 Yamaha Virago 250, 5000 mi. and well maintained.

Last edited by Wavelength; 01-15-2015 at 03:43 PM.
Wavelength is offline  
Sponsored Links
Advertisement
 
post #2 of 14 (permalink) Old 01-15-2015, 07:37 PM
Senior Member
 
Corsair's Avatar
 
Join Date: Mar 2011
Location: Gatineau QC Canada
Posts: 3,650
Garage
Is there some sort of shielding on the back pipe?

2009 Stratoliner S

A few things added and more stuff to follow


https://sites.google.com/site/vstar1100kb/
Corsair is offline  
post #3 of 14 (permalink) Old 01-15-2015, 10:07 PM Thread Starter
Member
 
Wavelength's Avatar
 
Join Date: Oct 2014
Location: Mims, FL: Home of the Flying Sunset Cans
Posts: 54
No, the back pipe just runs down normally to the muffler. The only thing is that crossover pipe/reservoir affair. The crossover pipe(1") runs from the forward end of the front cylinder muffler to the pipe connection into the rear cylinder. The reservoir is a flat container about 5"x5"x1" that sits directly under the mufflers. I don't know this type of system or exactly what it's purpose is. If someone else could possible measure the temp on their bike for a back-up check it would be very helpful. Many multimeters come with a temp sensor probe now. That is what I used. Thanks, Wavelength.

2009 Yamaha Virago 250, 5000mi.
Wavelength is offline  
Sponsored Links
Advertisement
 
post #4 of 14 (permalink) Old 01-16-2015, 09:00 AM
Senior Member
 
Sick Mick's Avatar
 
Join Date: Oct 2011
Location: Corona De Tucson, AZ
Posts: 2,181
So what is the temp of head pipe? That's really the only temp that's important on a motorcycle IMO.

Like you said, if exhaust gas is running through different contraptions....that is probably the reason for the temp difference at the muffler. If you had straight pipes on there, they would be close to the same temp at the ends.

Sick Mick* 2006 V Star 1100 Custom

--- Striping, lettering and paint by Sick Mick 6* Tree - 2" extended forks 21" front wheel - HK Sideburners - Progressive rear shock Pods Sick Mick solenoid delete - Spring seat - and other stuff
Sick Mick is offline  
post #5 of 14 (permalink) Old 01-16-2015, 01:48 PM Thread Starter
Member
 
Wavelength's Avatar
 
Join Date: Oct 2014
Location: Mims, FL: Home of the Flying Sunset Cans
Posts: 54
SM, Yea got to be something like that. The front pipe temp is 230 F. The exhaust is stock arrangement, probably for tuning and emissions. I haven't seen it before and don't know what it's for. Wavelength.

Found the parts diagram. Does anybody know what this stuff is for?

Parts Diagram: http://www.yamahapartspitstop.com/oe...797546/exhaust

Last edited by Wavelength; 01-16-2015 at 02:20 PM.
Wavelength is offline  
post #6 of 14 (permalink) Old 04-27-2015, 04:33 PM
Senior Member
 
BigBuddha76's Avatar
 
Join Date: Oct 2013
Location: Gulf Breeze, FL
Posts: 164
Garage
looks like to me part 12 is a dummy pipe (note no exhaust gasket). part 9 looks to be the real pipe feeding the main muffler assembly (part 1) which then flows from the lower muffler and come out of the top muffler at the same time.

yes I know its an old thread.
BigBuddha76 is offline  
post #7 of 14 (permalink) Old 04-27-2015, 04:59 PM
Senior Member
 
Join Date: Sep 2010
Location: Ohio
Posts: 163
Right, as far as I know the pipe coming out of the rear cylinder IS NOT where the exhaust actually comes out. It's just there for show. It really exits out the bottom or something. Weird.
Dave is offline  
post #8 of 14 (permalink) Old 04-27-2015, 05:59 PM Thread Starter
Member
 
Wavelength's Avatar
 
Join Date: Oct 2014
Location: Mims, FL: Home of the Flying Sunset Cans
Posts: 54
Red face Exhaust

Yea, As far as I can tell without an internal view, the flat reservoir-looking piece between the mufflers must equalize the pressure between the two. Piece 9 and 12 join together at the top of the rear cylinder in a common fitting(not shown). This looks like some #1 cylinder exhaust is fed to #2 cylinder exhaust via part 9. I think that sometimes exhaust pressure/vacuum can be used as a pump for positive crankcase ventilation, but I am not up on the theory of this.

250 Virago V-Twin 2009 5000mi.
Wavelength is offline  
post #9 of 14 (permalink) Old 04-28-2015, 08:15 AM
Junior Member
 
Join Date: Dec 2014
Posts: 17
Can confirm what others are saying. The rear cylinder exhaust pipe (the chrome one) is a dummy pipe until it passes the catalytic converter (not sure if it's called this on a bike but it's function is the same) which is under the bottom pipe that connects to the front cylinder. This is why Yamaha is clear to say that it's not a dual exhaust, but rather a dual exhaust pipe system since technically, exhaust comes out both.

Josh

2014 V-Star 250
learnfromhistory is offline  
post #10 of 14 (permalink) Old 04-28-2015, 09:20 AM Thread Starter
Member
 
Wavelength's Avatar
 
Join Date: Oct 2014
Location: Mims, FL: Home of the Flying Sunset Cans
Posts: 54
Thumbs up exhaust

Josh-That is VERY interesting to know. Thank You.

250 Virago V-Twin 2009 5000mi.
Wavelength is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Star Motorcycle Forums: Star Raider, V-Max, V-Star, Road-Star Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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

 
For the best viewing experience please update your browser to Google Chrome