Road Star Forum
Welcome, Guest
Please Login or Register.    Lost Password?
Re:MPG down after new plugs?
Go to bottom Post Reply Favoured: 0
TOPIC: Re:MPG down after new plugs?
#497397
professor8 (User)
Junior Boarder
Posts: 132
graphgraph
User Offline Click here to see the profile of this user
MPG down after new plugs? 11 Months, 3 Weeks ago  
I recently pulled the original stock plugs on my 04 R* and put in new Iridiums. Since doing this I have noticed my mpg has dropped from 42-44 to about 38 (or less). I didn't make any other changes at the time. I thought, if anything, I would get better mileage after changing the plugs.
Could new plugs cause the mpgs to drop?

The outside temps went up a bit over the last couple of weeks also - could this be cause for the suddenly poor mileage?

The bike is still running and sounding great...

-R
 
Logged Logged  
 
As different as we are, the road we travel is the same.
  The administrator has disabled public write access.
#497400
Blackroadie (User)
Sometimes I wish you were a pinata !
Platinum Boarder
Posts: 6890
graphgraph
User Online Now Click here to see the profile of this user
Gender: Male scottpaynter9228@gmail.com Location: Bluffton, Ohio
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
Odd. I could tell I had more power and the cylinders burnt better...causing a little better mileage. I havent heard of anybody putting in Iridiums and losing mpg's. Dont know about the temp...I never really notice any difference with mine. Lets see what others say.
 
Logged Logged  
 

...Scott
  The administrator has disabled public write access.
#497402
SKWEARpeg (User)
Platinum Boarder
Posts: 5265
graphgraph
User Online Now Click here to see the profile of this user
Gender: Male Location: Milton, Florida Birthdate: 1958-00-00
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
I'd check and make sure all the caps are pushed down tight on the plugs. Do you remember what you gaped them at?
What kind of plugs were in it before, and what did you use for replacements?
 
Logged Logged  
 
  The administrator has disabled public write access.
#497409
Blackroadie (User)
Sometimes I wish you were a pinata !
Platinum Boarder
Posts: 6890
graphgraph
User Online Now Click here to see the profile of this user
Gender: Male scottpaynter9228@gmail.com Location: Bluffton, Ohio
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
Iridiums are pre gapped...no touchy...delicate.
He took the factorys out.
 
Logged Logged  
 

...Scott
  The administrator has disabled public write access.
#497413
professor8 (User)
Junior Boarder
Posts: 132
graphgraph
User Offline Click here to see the profile of this user
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
As stated - I removed the original plugs - I think these were NGK. (The bike didn't have a lot of miles on it when I bought it.)
I opened the gap a bit on the iridiums to .034 per the manual. I've since rechecked the plugs (retorqued per spec) and reseated the boots. They seemed to be on tight before though. And the bike is running really good - just burning more fuel than normal.
 
Logged Logged  
 
As different as we are, the road we travel is the same.
  The administrator has disabled public write access.
#497417
Greysnake (User)
I'm so far behind I think I'm first.
Platinum Boarder
Posts: 10211
graphgraph
User Offline Click here to see the profile of this user
Gender: Male Location: Lawrenceburg,Kentucky. Birthdate: 1951-01-00
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
Thats called twisting the throttle syndrome. Feels like more power and you tend to twist alittle more.
 
Logged Logged  
 


06 Midnight Silverado
*nothing shines like a star*
  The administrator has disabled public write access.
#497423
professor8 (User)
Junior Boarder
Posts: 132
graphgraph
User Offline Click here to see the profile of this user
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
Could definitely be related to this syndrome
I'm on a fresh fuel refill right now after rechecking all connections/retightening/etc so I'll know better in about a week. I'm really trying to lay off the throttle though...but it's difficult - and not near as much fun!

I just want to make sure I work on one thing at a time without introducing any problems - getting ready to do the AIS removal next.
 
Logged Logged  
 
As different as we are, the road we travel is the same.
  The administrator has disabled public write access.
#497500
Questcap (User)
Platinum Boarder
Posts: 4394
graphgraph
User Offline Click here to see the profile of this user
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
Air temp definitely affects gas mileage, too.
 
Logged Logged  
 
Sig Pic deleted - larger than 450 pixels and 50 kb
  The administrator has disabled public write access.
#497519
SKWEARpeg (User)
Platinum Boarder
Posts: 5265
graphgraph
User Online Now Click here to see the profile of this user
Gender: Male Location: Milton, Florida Birthdate: 1958-00-00
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
Blackroadie wrote:
Iridiums are pre gapped...no touchy...delicate.
He took the factorys out.


Ouch! That's twice. I may have to put you on the payroll.
 
Logged Logged  
 
  The administrator has disabled public write access.
#497521
Blackroadie (User)
Sometimes I wish you were a pinata !
Platinum Boarder
Posts: 6890
graphgraph
User Online Now Click here to see the profile of this user
Gender: Male scottpaynter9228@gmail.com Location: Bluffton, Ohio
Re:MPG down after new plugs? 11 Months, 3 Weeks ago  
SKWEARpeg wrote:
Blackroadie wrote:
Iridiums are pre gapped...no touchy...delicate.
He took the factorys out.


Ouch! That's twice. I may have to put you on the payroll.

where do I sign up!
 
Logged Logged  
 

...Scott
  The administrator has disabled public write access.
Go to top Post Reply
Powered by FireBoardget the latest posts directly to your desktop
...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... ...................................................................... -->
New Forum Posts




The Road Star Clinic is a collaborative community of riders who archive and publish user contributed technical data about Yamaha Road Star motorcycles.

We also sponsor the creation and support of other community websites similar to our own. Inquiries about availability of a website for your community can be submitted to us via any "Contact Us" option on the Clinic.

Copyright 2003-2007 Road Star Clinic and its respective authors. Road Star Clinic is sponsored by the folks at MLSHomeQuest.com.