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I believe you have the same ignition as the GL's that I am familiar with. Timing is adjusted by rotating the pickup assembly plate on the rear of the camshaft. Usually you never have to adjust this after inital setup as there are no parts to wear. You have limited ability to play with it as is since they are already close to the maximum advance the camshaft geometry will allow. On the 650's the starter often has a hard time turning over the motor on startup because of preignition. A lot of the starter problems, in particular the slippery starter clutch are caused by premature ignition.

There was a modification of the automatic advance mechanism that was published on the French site that allowed for more advance at high speed without low speed preignition problems that you might want to try if you are trying to get more out of your machine at high RPMs. although it may be limited. The current advance mechnism reaches its maximum advance at 3500 rpm.
 

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Discussion Starter · #4 ·
ok i will get back to this bike in a week or two i have school and favors to get done before my stuff gets attention which sucks but w/e
 

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I believe you have the same ignition as the GL's that I am familiar with. Timing is adjusted by rotating the pickup assembly plate on the rear of the camshaft. Usually you never have to adjust this after inital setup as there are no parts to wear. You have limited ability to play with it as is since they are already close to the maximum advance the camshaft geometry will allow. On the 650's the starter often has a hard time turning over the motor on startup because of preignition. A lot of the starter problems, in particular the slippery starter clutch are caused by premature ignition.

There was a modification of the automatic advance mechanism that was published on the French site that allowed for more advance at high speed without low speed preignition problems that you might want to try if you are trying to get more out of your machine at high RPMs. although it may be limited. The current advance mechnism reaches its maximum advance at 3500 rpm.


Hi There Mr. Mayor




I wanted to ask if you think that going to cooler range plug might help w pre-ignition issues ? I'm afraid of leaning out and blowing up the way things are and I'm not going to screw with it's finicky air management/ Exhaust systems nor timing until I can get a better handle on it.



ThX



Jeff
 

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I've read several times about this alleged,"Pre-ignition" problem with the 650 models but I'm sceptical about it.I think that Honda just didn't allow for the heavier load on the battery and starter from the larger displacement of the engines requiring more inertia to start.

If I had a 650 I would do the Starter modification and service and also upgrade to the same 190 CCA batteries I use from the stock 140amp ones.



There are many myths that built up around these engines over the years many of which have been dispelled.Within 6 months of ownership some 7 years ago I had sorted the bad starting on my 1st CX by servicing the Starter motor and cleaning the carbs.From that time onwards both my CX500s start,"On-The-Button" and fire on both cylinders as they should even down to minus 5 Deg C.

The only time they don't is if left with the petcock off for a long period.In that case I either spray Starter Aerosol/Carb Brake cleaner/WD40 even into the carbs to help pull the fuel through the dried float bowls or release the float bowl drains to allow the bowls to fill and within seconds they return to normal.



People who have to take their bikes off the road for long periods due to harsh weather are caught between a rock-and a hard place.If they drain their float bowls so the fuel doesn't go stale the internal of the carbs tend to start getting a white powder forming.This is actually Aluminium oxide/rust but commonly mistaken for lime scale/calcium based deposits.This usually blocks the low idle circuits at some point.



If they leave fuel in it can go stale and leave a fuel patina on parts also causing problems down the line.

The best option is to start the bike,even in storage,at least once a month and ride it even if it's only a few feet to move wheels,clutch, and engine parts around and even electrical connections benefit from this as well.etc and keep the battery on a top-up charge and if possible allow the engine to get to normal running temperatures.



This can help avoid the usual,"Spring Dance" bikes being taken out of storage and not running right.







HTH
 

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Shep,

I have experienced a direct link with the timing and the starter. On one of my 650 rebuilds, I had problem starting the motor with it stalling on what seemed like Top Dead Center. Changed the starter to no avail. Checked timing and voila! I like to set timing as far ahead as possible, possibly under the false impression that it helps performance, so I still get the occasional hesitation on the starter when I start up the motor on a warm day after a good workout.

You do not want to play too much wiht advance timing. I remember being stranded with my CL350 a few decades ago because of a blown out piston while riding on the highway. I had set the timing for more advance and it was too much for the motor. I sorta knew there was too much advance on it because it would kick back occasionally on the kick starter when starting hot! The same happens with the 650 except the starter takes it instead of my leg.

As for cooler or hotter plugs, Nolavox, if you put more advance on the timing, your motor will run hotter and I believe cooler(higher heat number?) plugs may be in order, particularly in your neck of the woods, but you may have to play with it. If you use a cooler plug, it may prove a little finnicky on cold starts but should run fine the rest of the time anyway. The user manuals already allow for cooler plugs (DPR9 is described as best for long highway hauls), and there are several high tech ones available now (platimum, iridium etc.) I have had a set of platimums in my GL650 for close to 100k km now with good success.
 

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Shep,

I have experienced a direct link with the timing and the starter. On one of my 650 rebuilds, I had problem starting the motor with it stalling on what seemed like Top Dead Center. Changed the starter to no avail. Checked timing and voila! I like to set timing as far ahead as possible, possibly under the false impression that it helps performance, so I still get the occasional hesitation on the starter when I start up the motor on a warm day after a good workout.

You do not want to play too much wiht advance timing. I remember being stranded with my CL350 a few decades ago because of a blown out piston while riding on the highway. I had set the timing for more advance and it was too much for the motor. I sorta knew there was too much advance on it because it would kick back occasionally on the kick starter when starting hot! The same happens with the 650 except the starter takes it instead of my leg.

As for cooler or hotter plugs, Nolavox, if you put more advance on the timing, your motor will run hotter and I believe cooler(higher heat number?) plugs may be in order, particularly in your neck of the woods, but you may have to play with it. If you use a cooler plug, it may prove a little finnicky on cold starts but should run fine the rest of the time anyway. The user manuals already allow for cooler plugs (DPR9 is described as best for long highway hauls), and there are several high tech ones available now (platimum, iridium etc.) I have had a set of platimums in my GL650 for close to 100k km now with good success.


Thanks for the reply... I'm not sure if pre ignition in the traditional sense of heat or valve issues is the same as a timing related misfire on startup. I don't think it matters what it's called as long as it does not keep happening leading to catastrophic failure during running... It sounds like the 650 issue might be a combination of advance and having a pool of unburnt fuel in the jugs on startup. I am more concerned with pre ignition on a hot engine and not ignition kickback. I am going to try and be more vigilant in shutting my petcock and doing a little after run...not dry enough to kill the motor, just empty some of the fuel in the bowls so it does not flow into the jugs etc... A thread about fuel getting into the crankcase (oil) is one reason I do this as well as the fact floats don't normally stick down unless the motor has not been run for a longer long time.



@Shep... an interesting conundrum. Dammed if I do, or don't do...
like everything else in life in some ways a "compromise"




I wonder what Thomas will think about this in a week or two when he returns to "normalcy"
sorry to jack this...



Moral of the story for me: I think I'm going to put on exhaust temp gauge that I have laying around before I go messing with the timing, or fuel / air / exhaust management.
 

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His bike is an 81 CX, so it has the CDI ignition and the Ignitech would be applicable if he chose to go that route.



But it would be good to understand the reason for wanting to make a timing change in the first place, especially since that is almost never an issue with these bikes.



Perhaps it is to correct some problem and timing is suspected to be the culprit.
 

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Shep,

I sorta knew there was too much advance on it because it would kick back occasionally on the kick starter when starting hot! The same happens with the 650 except the starter takes it instead of my leg.


Classic symptons of a tired starter motor.

I`m not convinced these bikes have `too much ignition advance` as a bike with a good starting system will not show any of these problems.

Altering the ignition timing would merely mask the symptons instead of tackling the root cause.

You might want to consider doing the earth strap mod on the 650.





As for fuel `going off`, `stale` or otherwise deteriorating i can only say i`ve never seen it as a problem.

The Ratwing has been off the road for two years.

The fuel in the tank is two years old.

It started up just fine - as does one of my other 650`s which has also been in semi-retirement for the same period of time.

I`ll admit the fuel does evaporate from the float bowls rather rapidly (possibly the `higher volatile` elements of the petrol) , and can take some priming to ease starting, but converting a vacuum petcock to manual will help a lot with that....
 

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Discussion Starter · #16 ·
I would love to go ignitech but my budget is too tight, I figured the problem out. someone has put TI coils on the bike and it wont run right because it needs cdi coils so i Ebay'd those beasts and i should be rollin by friday
 

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I wanted to ask if you think that going to cooler range plug might help w pre-ignition issues ? I'm afraid of leaning out and blowing up the way things are and I'm not going to screw with it's finicky air management/ Exhaust systems nor timing until I can get a better handle on it.
A colder plug will not change when it fires, the heat range of a plug has to do with at what temperature range it will effectively self-clean the carbon reside off the insulator that's left behind after combustion. You only use a colder plug when the engine is going to be operated under a fairly heavy load most of the time, a hotter one if your riving is virtually all stop and go or it's very cold outside.
 
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