Steve Saunders Goldwing Forums banner

1 - 20 of 22 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
I am wondering if anyone has any info on porting and polishing cylinder heads off of a 1984 Gl 1200? Are there any areas in the casting that are thin and need to be avoided? Do these motors respond to one port better than the other(exhaust more than intake or vise versa?). I am thankful for any and all knowledge shared. Thank you for your time!!:nerd:
 

·
Administrator
02 GL1800 w/Auto Pilot
Joined
·
59,283 Posts
in most cases, that is wasted effort and can actually be detrimental to efficient fuel air mixing for making good horsepower.

on our Goldwings, it is not helpful at all, as the compression ratios are too low to worry about it.

and use the lowest octane number on the gas pump... the higher octanes will only build up carbon soot on the engine parts.
 

·
Premium Member
Joined
·
223 Posts
This reminds me of an old article that ran in Cycle Magazine. The author was trying to raise the horsepower on a Yamaha TT500. The port flow was played with, by grinding them in several configurations. Their best results came from filling in the low side of the ports, around the valve guide, and taking out a bit of metal on the opposite side. Then it was tested on a flow bench. The results surprised many. Changing the radius of the port made it work better. A larger opening did nothing.
 

·
Premium Member
Joined
·
6,379 Posts
This reminds me of an old article that ran in Cycle Magazine. The author was trying to raise the horsepower on a Yamaha TT500. The port flow was played with, by grinding them in several configurations. Their best results came from filling in the low side of the ports, around the valve guide, and taking out a bit of metal on the opposite side. Then it was tested on a flow bench. The results surprised many. Changing the radius of the port made it work better. A larger opening did nothing.
Yeah, Like everyone is saying. Everything is a compromise. If you enlarge the port size it can slow down the air/fuel charge and the fuel can fall out of suspension at low RPM. That is the RPM we spend most of our time running. I wouldn't waste any time.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #8
Thank you AzGl1800! I have only worked on cars,trucks,and various small engines up till now. I am learning about these bikes but they are very unique to say the least!
 

·
Administrator
02 GL1800 w/Auto Pilot
Joined
·
59,283 Posts
Thank you AzGl1800! I have only worked on cars,trucks,and various small engines up till now. I am learning about these bikes but they are very unique to say the least!

The Goldwings are a fairly slow turning, high torque motor.

we run them mostly below half or even a third of their max RPM....

therefore, it is just an exercise in futility to try and increase their horsepower by any means.
 

·
Registered
Joined
·
1,772 Posts
I did port and polish my 82 1100,corrected the mismatched fit between the head,and polished the runners into the carb and that's all I did,nothing opened up but just matched stuff and I can't say it had more power but it did come alive after 9,000 rpm,I don't know what the motor would actually turn but 12,000 was a breeze,a mechanic in Apache Junction Az Jim had an 83 ( I think) that he had twin Weber on it and had a 15000 rpm limiter on it,he had been a wing mechanic for a long time,I don't know if the motor had been worked on.
So I would agree with the rest on not gaining any hp but the fun factor of a fast wing was awsome.AZ1800 might have seen the bike
 
  • Like
Reactions: limpy45

·
Premium Member
Joined
·
740 Posts
Funny but my 82 1100 was screaming for me to get off the throttle at around 6500 RPM or so. 11000 ? Don't think I could stand the noise! LOL Must be a clean machine.
 

·
Registered
Joined
·
1,772 Posts
Well it certainly surprised me the first time it ran past 10000,it doesn't seem to be working hard but of course that senerio wasent an everyday thing but I did have another exhaust I built for it,the whole bike was less than 500 pounds.i suspect the exhaust was the key to the performance.
 

Attachments

·
Registered
Joined
·
1,772 Posts
I did build another exhaust for it,from a Suzuki GSX1000 and that's when it came alive.It would do power wheelies but it would scare the crap out of me at over 100, for some reason it didn't care for high speed.
 

Attachments

·
Registered
Joined
·
4 Posts
Discussion Starter #15
Pure Texas that sounds like you had a lot of fun building and riding that one! I think what I am going to do is polish the casting marks out of the ports,cc all of them and port match them. Basically try to clean up what is there!
 

·
Registered
Joined
·
1,772 Posts
Yep that's all i did,from my racing days I know if there is any mismatched areas in the fuel flow system then cleaning it up helps but then we were working on 2 stroke motors and every little bit helped.
 

·
Registered
Joined
·
222 Posts
Shortly after I got back into Gold Wings again after a long and boring marriage and I picked up a 80 GL1100 I was to a bike show. A vendor had all sorts of stuff on display for HD's. I asked him if he had any soup up stuff for GL's. He took me aside and asked, have you ever raced anyone and lost? I said no have not raced anyone. He says, we used to try various things when the GL's first hit the streets. Nothing much other than a super charger really helped. He said they are strong running and go like hell the way they are, don't mess with it! Just sold it last fall. Now I have another. Don't know why, guess i need a "toy" to play with???
 

·
Registered
Joined
·
460 Posts
All I ever did to mine was run some steel wool around a circular wire brush on my drill to smooth the intake tubes, and add a K&N air filter. I get awesome low end torque but always did. I wouldnt mess with the heads. I run my Goldwing hard really hard, if your going to run hard make sure you change your timing belts.
 

·
Official "Cheeky Plonker"
Joined
·
1,199 Posts
I remember a conversation with the owner of my local performance engine shop when I took my 1100 heads in for rebuild a few years ago.


Tim: Would you like me to polish and port them for you?
Me: Man, it's only an 80 horse power motor.
Tim: I can make it a hundred!


I turned it down, cos I thought he was most likely exaggerating and I was on a budget at the time anyway, but who knows? He might've had some tricks up his sleeve.
 

·
Administrator
Joined
·
25,763 Posts
I remember a conversation with the owner of my local performance engine shop when I took my 1100 heads in for rebuild a few years ago.


Tim: Would you like me to polish and port them for you?
Me: Man, it's only an 80 horse power motor.
Tim: I can make it a hundred!


I turned it down, cos I thought he was most likely exaggerating and I was on a budget at the time anyway, but who knows? He might've had some tricks up his sleeve.
I have serious doubts a port and polish would produce a 25% gain.
 
1 - 20 of 22 Posts
Top