89 EVO detonation

[ChipG]

 I have an 89 Tourglide ultra I've been playing with for about 10 years. The engine has an EV27 cam, Crane ignition, SE heads an S&S carb and a Bassani 2 into 1 pipe.
In the morning it runs great, cold air, but in the afternoon, it seems like its getting hot as it starts detonating up any hill or bump. Down shifting helps. I figured it might be the VOES so I replaced it with a new one.  Is there a way to check that the ignition is responding to the VOES ?  What other things might cause the symptoms I've described ?   
Oh and the belt squeak's like a bitch.

  Thanks for any help

  Chip

[BluHarley]

Check the teeth on the belt, or alignment.  Mine was chirping.  I took it to 3 shops.  One said it was the speedo cable, another said my 6th gear was shot and I needed a $3000 tranny rebuild, and I even forget what the other idiot said.  Professional shops.  And then one day I'm under it spinning the back wheel, and I saw teeth breaking away, and a row of missing teeth, about 10 of them. 

[BluHarley]

5th gear I meant.

[ChipG]

The belt was replaced last summer.  Its almost like a continuous rubber squeegy noise.

[BluHarley]

Alignment.

[War Horse]

+1 on the alignment, but also check for to tight of a belt, that will squeak like crazy to.

[rdkng]

HD has a $20 tool to properly check the tightness of the belt.
A loose belt will frequently chirp.  You didnt mention if you changed
the pulleys with the belt, but thats recommended if mileage is high.

If the pining is a fairly new event, it may be gas related, as most places
now have seasonal mixes. plus ethanol also changes the 'quality' of the gas,
so many high compression motors are having new issues.  (an EV27 & SE
heads has a fairly high psi)  May try some octane boost to see if it helps.

I did the VOES adjustments, cant recall what I set it to, but no major
improvements for me.  Backing off the timing a touch may help i.e. from
maybe 35 advance to 33 or so.. 

rdkng     

[War Horse]

Got to thinking, that old of a bike may have an issue with carbon build up on the pistons, ie. glowing red hot carbon ignites fuel before the plug fires.. Just another thing to consider.

Run some Marvel Mystery Oil in the gas every tank, it's 2oz per 5 gallons of gas. Been running it for 39 years, it works.

[ChipG]

  Bike is old, Engine isn't. I feel the problem is in the ignition or VOES. I've eliminated the VOES as being inoperable but, the signal may not be getting to the ignition. Next step is to check the wireing to the ignition, then check the timing.
  On the belt, I'll recheck  the allignment and tightness.

  Thanks for the help

  Chip

[HogMike]

I have an 89 Tourglide ultra I've been playing with for about 10 years. The engine has an EV27 cam, Crane ignition, SE heads an S&S carb and a Bassani 2 into 1 pipe.
In the morning it runs great, cold air, but in the afternoon, it seems like its getting hot as it starts detonating up any hill or bump. Down shifting helps. I figured it might be the VOES so I replaced it with a new one.  Is there a way to check that the ignition is responding to the VOES ?  What other things might cause the symptoms I've described ?   
Oh and the belt squeak's like a bitch.

  Thanks for any help

Couple of things to consider:
You can set your advance curve to come in a little softer (later) a couple degrees at a time until the ping goes away.
You can get an adjustable VOES and also set the retard to come in at a lower pressure.
I had that same issue with my EVO, never did get it to run the way I wanted!
Takes some playing around. More revs (down-shifting) works.
Like others said, good gas, octane booster, all the usual tricks.
Good luck.










































  Chip

[shovhd]

I'm no pro, but I've done several things to eliminate the detonation on my 11:1 evo. Colder plugs, tune the carb a little richer, back the timing off a bit especially from 2000 to 3500, change my VOES to 7"hg. I can now run on 94 octane with ease and 92 if I'm careful. If this just started check for an intake leak, a little leaner = detonation. As mention earlier, carbon will cause detonation. If you can program your ignition, back it off a bit. You can add an LED to indicate if your VOES is working. Here are a few links to reads that I have found very helpful:

Detonation
http://www.americanrider.com/output.cfm?id=1021915
http://www.wildwestcycle.com/f_deto.html

Timing
http://www.wildwestcycle.com/f_timing1.html
http://harleytechtalk.com/htt/index.php/topic,941.0.html

VOES
http://www.wildwestcycle.com/f_voes.html

Plugs
http://www.carcraft.com/howto/116_0703_spark_plug_guide/index.html

Lot's of reading...sorry.

Good luck

[ChipG]

Thanks for all the suggestions

[kenkla]

ChipG
   Try rubbing a bar of soap on the inside of the belt. My 98 fatboy had the same squeek, and that was the cure.

[karlsbike]

As suggested, you could have
a) carbon build-up on pistons (try spraying water mist directly into carb throat while running - airfilter off)
b) intake air leak (check with wd-40, ether or whatever spray around seals; check for rpm changes)
c) exhaust leak (listen & smell at the heads exhaust ports)
d) spark plug too hot (try a colder grade)
d) ignition too advanced (try retarding the pick-up plate 1-2 degrees)