Steve Saunders Goldwing Forums banner

Status
Not open for further replies.
1 - 10 of 10 Posts

·
Premium Member
Joined
·
20 Posts
Discussion Starter #1
imported post

Hi all,



I have a problem with a 1987 GL 1200 Aspencade.

The bike starts fine and it also runs very well as far as acceleration and speed are concerned. The problem is that when I initially try to accelerate it has a slight flat spot and then accelerates fine. The other problem is it takes a while for the revs to die down when releasing the throttle when changing gears. I have checked the fuel mixture screws, and also balanced the carbs which are now exactly as they should be. The tickover revs are a little eratic and fluctuate netween around 700 to 900 rpm.

If I try to adjust the idling speed nothing happens at first and then it will jump to around 2200 rpm, and when I then turn the idling speed down, again nothing happens and then it jumps back to the 700-900 rpm. I was wondering if it could have something to do with the slow air cut off valve but I am not sure how this effects the idling system.



Any ideas,



Mick.
 

·
Premium Member
Joined
·
1,215 Posts
imported post

Sounds like a good carb. sync. is in order, but you stated you did that.

Jim
 

·
Junior Grue
Joined
·
8,153 Posts
imported post

I don't know anything about the "slow air cut off valve" as Canadian models don't have it.:D

From what you describe I would be looking for vacuum leaks in one or more of the runners between the carburetors and heads.
 

·
Premium Member
Joined
·
802 Posts
imported post

I agreee with Ken, classic symptom of a vacuum leak. There is only one vacuum line on the 1200 and it goes from the left side carb, #4, and goes to a Tee fitting up to the ECU.
 

·
Premium Member
Joined
·
802 Posts
imported post

Not to mean that is the only place you can have a vacuum leak. There are plenty of others like the O-rings below each intake tube. Also the Anti backfire valve under the carb intake manifold.
 

·
Premium Member
Joined
·
472 Posts
imported post

take a can of starter fluid, spray it around the intake elbows and vacume lines. do this with engine on idle. if it speeds up you have found your leak. walkabout :)
 

·
Junior Grue
Joined
·
8,153 Posts
imported post

John it's up to Mick to find the vacuum leak as we're not there.

Of course it would only take me five minutes to pack my bags if Mick sends me a ticket.:ROFL::ROFL:
 

·
Premium Member
Joined
·
20 Posts
Discussion Starter #8
imported post

Thanks to everyone for the tips so far.



I will check for vac leaks. As I stated I have syncronised the carbs as described on Steve Saunders video and they are 100% in sync now. I can see the sense in a vac leak causing the flat spot, but not the idling screw not making any difference and then jumping to over 2000 rpm. Its like something is sticking and then releasing suddenly. ?.


Just for the record, I have sprayed and lubricated all linkages and controlled them to make sure they were not sticking in any way.



Mick.
 

·
Premium Member
Joined
·
1,424 Posts
imported post

clean out the diaphrams and of course the primaries are good to go...re-sync...let em slap back hard and repeat
 

·
Busdriver
Joined
·
1,037 Posts
imported post

Clean your carb slides, sounds like one or more may be dirty and sticking. Just pull the air filter snd give each a short shot of carb cleaner spray, then wash with a little WD40 and move the slide back and forth with a finger.
Worked for me.
 
1 - 10 of 10 Posts
Status
Not open for further replies.
Top