85 GL1200 straight pipes vs mufflers


Information and questions on GL1200 Goldwings (1984-1987)
Post Reply
roallen
Posts: 9
Joined: Fri Apr 17, 2015 4:14 am
Location: portland, oregon
Motorcycle: 82 gl1100

85 GL1200 straight pipes vs mufflers

Post by roallen »



hello all
i just got a 85 GL1200 A
the PO had removed the stock mufflers for whatever reason and the bike now has straight pipes going the entire length of the bike. what i need to know is running the straight pipes going to damage the motor? from what i've been able to find it's a 50/50 split between people saying yes and no
help me out guys
thanks



sportsfreaked
Posts: 370
Joined: Fri Mar 13, 2015 7:23 am
Location: Independence, MO
Motorcycle: 1981 Honda Goldwing Interstate GL1100I
1985 Honda Goldwing Limited Edition gl1200

Re: 85 GL1200 straight pipes vs mufflers

Post by sportsfreaked »

Ok I'm no expert on exhaust but I don't see how it could hurt the motor. Having straight pipes back just means less heat and back pressure and more noise. I don't think you will gain anymore power you may lose some. You may have to add different jets for the carbs. I'm sure others will chime and educate as well. Please don't take my opinion as gospel. I'm looking forward to what others have to say on the subject. Best of luck and enjoy the new ride! Not sure if you are new but you have found one of the best site on the net IMO for Goldwing owners. Plenty of help and knowledge here.
Thanks to all who answer and help. It is greatly appreciated!
Ed

User avatar
virgilmobile
Posts: 9082
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: 85 GL1200 straight pipes vs mufflers

Post by virgilmobile »

If you want it to preform like OEM engineering..Keep it OEM.
The exhaust system is engineered to create just the right amount of flow resistance.(back pressure) for the engine.
If you change the restriction arbitrarily there can be adverse effect.
This is refered to a "tuned exhaust"...There's way too much reading about this subject when it comes to "tuning" a Harley with after market pipes....Just adding a very small metal ring near the tail end will change the back pressure and affect the power curve...
Only a before and after dyno test can determine....
You can also just leave it and see what happens....Maybe the pipes will be close enough to work....

User avatar
Rusty Bike
Posts: 376
Joined: Sun Feb 28, 2016 1:55 pm
Location: New castle, PA
Motorcycle: 86 GL1200 SEi, 98 Valkyrie Std, 78 Yamaha XS750SE, 86 Honda XL125, 4.5 HP belt drive Minibike my dad built, foot clutch!

Re: 85 GL1200 straight pipes vs mufflers

Post by Rusty Bike »

Will it hurt the engine...Maybe. Will it hurt your hearing and piss off the neighbors, probably.

Engines do not like to run lean, you may melt a piston. Air fuel mixture is a balancing act, a tricky one at that. Unless you have excellent knowledge of engine tuning and access to hi tech engine test equipment, the best move would be to put it back to stock. Air box, filter, jets, pipes are a finely engineered system that took most of a century to develop. Pretty tough for a back yard mechanic to improve. JMO of course...



Post Reply