[alanz]

imported post

I have a '88 GL1500 and some time ago I fitted a 4 degree trigger wheel. It felt like it made a difference at low revs to help the hesitation that the early 1500's were prone to. However, recently I have noticed that it is preigniting (pinking, or pinging - depends where you come form), even from 3000 revs in top gear if I give it a reasonable amount of throttle. I am sure it wasn't like that when I first installed the trigger wheel and I even think it is getting worse. The minimum octane we can purchase here is 91 and that is what I have been using.
I can easily change it back to the original trigger wheel but I don't really think that is the problem. Can anyone suggest another reason for the ignition being overly advanced on acceleration.

 

[alanz]

imported post

Thanks for your reply and I appreciate what you are saying. It's just that it was working fine for some time - no detonation when it was first installed, because it was one thing I was looking for. I have just looked up my records and I installed it exactly 1 year ago and I have done 7000 miles since. I noticed a bit of pinging a few mo0nths ago but it was not that bad but now I am sure that the detonation is getting slowly worse. When I rode it today it was very audile even when pulling away at 3000 revs in OD.

I can't understand how the trigger wheel would have that effect. I would expect it to cause problems right from the start if it was going to.

I am wondering if the plugs are starting to wear out. Anybody got any thoughts about whether that would cause these symptoms.

And before anybody asks - No, I haven't looked at them yet. The thought only just occured to me and I thought I might get some advice before I take all that plastic off to get at the plugs.

Thanks

 

[alanz]

imported post

Thanks for the replies, guys.

I'll work through the lists and see what I come up with. On reflection it was much worse after I had filledthe tank. Maybe a bad batch of fuel although that is not common, here, in New Zealand. Guess it could happen though.

I think our fuel comes from Indonesia or in that region somewhere. Not sure if they change the blend for the seasons as we don't have such drastic changes in temperature throughout the year.

Everything else has been pretty much the same. Tires are checked regularly, and I was riding solo so the load was less than normal.

I think I will drain the tank and try a different fuel to see if that makes a difference and then try a top end cleaner.

Thanks for your help.

Al

 

[alanz]

imported post

Hi Eamon,

I don't think carbon will be a problem, either.

Today I pulled all the plastic off and started checking a few things.

The plugs seemed fine and they certainly hadn't carboned up, however I replaced them with new DPR8EA-9's and that made no difference.

Checked the timing at idle and it was perfect. Put a vacuum gauge on the ECM and that appeared to be working although there is no way of telling if it is advancing the ignition too far.

Put the original trigger wheel back in and although that has reduced the pinging considerably I can still hear it when I load it up even at higher revs.

Still open to any other suggestions if anyone has any more ideas.

Thanks,



Al Campbell

 

[alanz]

imported post

Thanks guys,

Looks like it is getting closer and closer to having to take one of the heads off for a look. Obviously want to leave that as a last resort.

Will try to see if our GM dealers carry the Top Cleaner that Vic is talking about.

Cheers

Al

 

[alanz]

imported post

Vic,

Tried to source the Top Cleaner from the local GM dealer but they don't stock it and hadn't heard of it. Our GM stuff is all Aussie Holden (great cars) not American.

However I did find a similar product made for Yamaha marine engines. Sounds like it does the same thing and this is also applied by spraying down the intake.

It is recommended that you change the oil, filter and plugs after using it so it might take me a little while to organise that.

Twisty,

Thanks for your advice also. I was thinking about the compression test but I will have to try and source a compression gauge that will fit down the hole. Mind you if it is carbon, it may only be a hot spot rather than over-compression. Is that possible or am I oversimplifying it?

Your comment about the fuel filter has also just rung a bell. I record all my fuel consumption figures and at about the time when this pinging got really noticeable I noted that the fuel consumption had jumped from 40 mpg (Imperial) to 44 mpg. This was basically from one tank to the next and I was patting myself on the back because I thought it was my skillful driving that was saving me some gas. I have since put about 6 tanks of gas through and they have all been about the same even when I took it for a bit of a blast to try to clean it out.

I will see if I can get a replacement one and check it out.

Will let you know how I get on in the next day or two.

Al from New Zealand

 

[alanz]

imported post

Twisty,

Thanks for that - more things I can look at.

I will check the fuel filter in the morning - time for bed over here, now.

Will let you know how I get on, thanks.

 

[alanz]

imported post

I've had a 'look' at my vaccuum hoses and they seem to be ok, however, that is only the ones that I can see. As everyone, here, knows they go all over the place and you can't check them all until you pull the bike apart. I will add it to my list. I realise this is going to take some time.

You are right about the supply of parts. The Gold Wing is not the most common bike over here and the parts supply is not good and very expensive. I tend to buy from the US over the Internet but that can take a bit of time.

The cost of fuel here is NZ$1.52 = CAN$1.21 = US$1.03.

So that actually compares pretty well with your prices. We thought we were hard done by because the prices have skyrocketed. Guess it is happening everywhere.

 

[alanz]

imported post

Ok, I have just replaced the fuel filter. When I took it out it looked ok and I could blow through it without any restriction but I figured it was worth replacing just to eliminate it out of the equation.

Have just taken it for a ride and the pinging is still there.

I am pretty sure this happens in all gears but it is a bit harder to detect in the lower gears now that I have replaced the 4 degree trigger wheel. But here's the scenario - 4th gear, just over 1500 revs - open the throttle and can feel the load coming on. No pinging immediately until the revs start to get up and then seems worse about the 3000 revs but can also be detected up at 4000-4500 revs. If I ease up on the throttle a bit - ie not accelerating so hard then it's not a problem.

At this time I have noticed that the exhaust colour is much lighter than it normally is. Usually the pipes are black and sooty and this is normal for all the vehicles here, since they changed to unleaded years ago.

I noticed the pipe colour before I took it for a ride and it is still like that. Both sides are the same. If it was a fuel blockage in the carb it would be more than a coincidence if both blocked at the same time. If one was blocked would that make just one side lean and not the other or is there some balance there that evens them up?



Vic,

where did you get the numbers for the total advance. I have a Clymers manual and a Honda Manual for the '88, but I haven't seen those figures - unless I am looking in the wrong place.

I have checked the timing with a strobe light and it is definitely advancing but for all I know it could be advancing way too much.

I have checked the Engine Control Module as per the instruction manual and it says that the engine should begin to speed up when a certain amount of vacuum is applied and then decrease when it gets to a higher level. Mine does that but again I don't know if it is advancing too much. I guess it is likely that it is working ok but without all the right numbers I can't eliminate it completely.

There are so many vacuum hoses in there and most are buried fairly deep inside and not easily visible. Just because the ones I can see are ok I realise that can't be eliminated as a factor either. Would you recommend taking the carbs out and cleaning them out and then that would also give me better access to check all the hoses down there? Is there any particular hoses that would cause the engine to run lean or advance the ignition if they are leaking? (Sorry, realise that is a bit of an open question).

Please don't give Twisty a hard time - he's doing his best to help - and you two guys are the only ones that have stuck with my thread and continued offering help. I know it is going to be some small thing (I hope) that I am missing so all the advice given will be considered. I have a fairly logical mind and enjoy tinkering with mechanical things (although this could test my patients a bit) and hope that this experience will help me learn more and more about how these great machines work.

 

[alanz]

imported post

Ok, thanks for that. I will start working on the hoses and carb when I get home from work, today.

Just going back to the timing, so I get it clear in my head. Vic, you seem to have the numbers - when I put the strobe light on it what should I expect to see. When in neutral and I increase throttle, the timing advances (how many degrees?). Is this done electronically by revs, or by vacuum, or both.

If I did the same thing in 4th or 5th gear will I see a difference with the strobe light?

If you can give me some specific numbers or a sequence to run through it would be appreciated. My manual only says to put it into gear and there should be an increase in revs.

You asked about the timing belt. When I replaced the trigger wheel I had to make sure the belts were lined up properly and they appeared to be in good condition.