Sometimes compression: the kicker would go straight through

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gpp3442
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Sometimes compression: the kicker would go straight through

#1

Post by gpp3442 » Sun Sep 25, 2005 5:54 am

Gentlemen,
My 57 pan is up and running. No problems all summer, except her usual shyness of starting in front of large crowds. When I went to start her this morning, the kicker would go straight through. I removed the plug and kicked to feel if there was any compression, on some kicks there is, but just slight to none. Rode nearly 100 miles last Sunday, with multiple start/stops and had no problems. Where may the problem be?

P.S.
Thanks to you all who helped me over this past winter/spring to get her running.

Thanks,
George III



mbskeam
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Re: Sometimes compression

#2

Post by mbskeam » Sun Sep 25, 2005 6:12 am

hello,
well it sounds like a valve issue,
are the valves set properly that is the 1st thing I would look at
before my rebuild it would do this some times , this was from the guides being way worn out, this let the valve hang up or off to the side and not close right.
or a valve guide is to tight and a valve is sticking open.
check push rods then do a compression test and see what you get.

mbskeam

gpp3442
Posts: 32
Joined: Sat Jul 14, 2007 3:22 pm

Re: Sometimes compression

#3

Post by gpp3442 » Sun Sep 25, 2005 6:28 am

mbskeam,
I had earlier problems with the valves, as they were way to tight and she would not start up once she was hot. I loosened them up, but that was months ago,
so now they may be too loose? and they could be pulled down and not seated right? is this what you are saying?

Thanks,
George III

Cotten
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Re: Sometimes compression

#4

Post by Cotten » Sun Sep 25, 2005 2:33 pm

George!

What cam are you running?
(Some performance cams with excessive overlap will not display much compression when kicked slowly.)

mbskeam
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Re: Sometimes compression

#5

Post by mbskeam » Sun Sep 25, 2005 3:39 pm

hello,
no I was saying that the valve s might be to tight, ie. OPEN on the comp. stroke
do you run solids? if so check them. its free
mbkeam

gpp3442
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Re: Sometimes compression

#6

Post by gpp3442 » Sun Sep 25, 2005 4:46 pm

Gentlemen,
valves check out fine(solids).
Mr. Cotten I have a flh cam.
Still,I have minimal compression and nowhere enough to turn over the motor.
Could there be problems with the kickstart shaft/gears?
Thanks,
George III

Cotten
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Re: Sometimes compression

#7

Post by Cotten » Sun Sep 25, 2005 5:02 pm

Is your clutch slipping?

Check the pedal geometry first, especially if you choose tighten your dampener.

(Or the linkage if you have one of those ultramodern moustraps.)

gpp3442
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Re: Sometimes compression

#8

Post by gpp3442 » Mon Sep 26, 2005 1:20 am

Mr Cotten,
Yes, Yes, Yes.
I went in and checked kick shaft all seemed to be alright.
But, Yes my clutch was slipping last time out and was all slacked out.
Buttoned Her up and was up and running.
Now I really still don't understand how this effected my situation(Explanation?)
Thank You both.
George III

P.S. I also experienced a loss of voltage in my battery after I took her out this afternoon
12+ VOLTS down to 9.8. Have her on the charger now. All connections look good.
Maybe generator? This bike was down for 15 years with the top and bottom being done in 1990 then sat till this past winter. Noticed the lights were dim then got brighter with a pull of the throttle. I will look through pasts posts, if any help could be given here it would be greatly appreciated. Thanks.

Billy
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Re: Sometimes compression

#9

Post by Billy » Mon Sep 26, 2005 6:25 am

my 2 cents,
w/slipping clutch yer motor doesn't spin over as it should (due to slipping clutch)......SO you do NOT get full rotations of motor if slipping...when kicking or otherwise.....(fix first)

Then;
As far as compression, test again, (record readings) Then add a spoon-ful of motor oil to each spark plug hole, then Re-test, if readings are suddenly much higher you can suspect a ring/sealing issue. As the oil will form a seal as Good rings should do..
The reason for this 'test' is to determine if you have issues w/rings, cylinder bores, etc..

Or top end/ valves guides etc..If readings stay about the same but are still low, suspect top end, valves not seating properly, etc.....

kell
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Re: Sometimes compression

#10

Post by kell » Tue Sep 27, 2005 3:41 am

gpp
If revving it makes the light brighter, that power had to come from somewhere, which means the generator works, right?
First thing I'd check for a short somewhere on the bike. Because it sounds like something's draining the battery. Or else the voltage regulator is going south. (Could be a bad battery too).

gpp3442
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Re: Sometimes compression

#11

Post by gpp3442 » Tue Sep 27, 2005 5:52 am

Mr Kell,
Thank you for your reply, I'm glad you did. My inexperience has been helped along with your past help. Last time the electrical problem was in the ignition post. Battery is new this season
but as you probably know these 12v batteries seem to be a short lived product. First off I have a had constant battles with my point set, I've seen past posts where you manufacture a product that might solve some of these issues. I do not have the stock set-up for a 57 but the newer style points. Can you please lead me to your company. I have owned this bike for over 15 years but only just started this past year to try to work on it myself. I'm still learning something each time I try do something. I still don't know her as intimately as I would like to,
sometimes I feel I'm getting there, she starts on the first kick etc.. but after a few rides the valves need adjusting, timing is off etc...As far as the voltage regulator(it says bosch-warner on it)is this something that can be switched out easily with the service manuals help. Ive read somewhere about polarization? look foward to finding out about your point set-up.
I also been thinking about going to the gel battery will this have any electrical effects on any of my set-ups?
Thanks,
George III

mbskeam
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Re: Sometimes compression

#12

Post by mbskeam » Tue Sep 27, 2005 6:14 am

hello,
if your valves needing to be set that often, you might need to change the lock nuts on the adj. screws. it helped on mine as they would back off and I know they were tight.

on the elect. I'll pass the hat to someone else, as I know how to but cant explane ,go figure.
mbskeam

gpp3442
Posts: 32
Joined: Sat Jul 14, 2007 3:22 pm

Re: Sometimes compression

#13

Post by gpp3442 » Tue Sep 27, 2005 8:32 pm

Kell,
I charged the battery and get 12.78 soon as i turn the ignition it goes down to 6-7 max.
Bad battery? I cant seem to find a short anywhere. I read in another thread about when you change the battery to polarize the generator. I still do not get this?
Thanks,
George III

kell
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Re: Sometimes compression

#14

Post by kell » Wed Sep 28, 2005 4:02 am

Right now don't try to find out where the short is, just test to see if there is one. You can use a taillight bulb, or a meter on the current measuring setting, splicing it in to one of the battery leads then turn the key. I say splice but of course don't splice anything, just take the wire off the battery post and connect the leads of the bulb or meter to the wire and the battery post.

If the points are closed you will get a current, so to avoid getting fooled by that, make sure the points are open or disconnect the coil. Turn all lights off, of course.

Then when you turn the key if the bulb glows or you get a reading on the meter you have a short. Bright bulb or lotta amps on the meter ==> bad short.

You can go to the new forum and read about my ignition device in the "commercial" classified section.

You can run your bike on a "gel" cell, although nowadays those sealed batteries don't use an actual gel anymore, they have replaced gel with a better system. Sealed "AGM" (absorbed glass mat, which has replaced gel) batteries are actually superior to wet batteries in most ways. They are more resistance to shock and vibration, for one.

About polarization, yes you are supposed to polarize a mechanical generator. I never used a mechanical regulator so I don't polarize, but from what I've read it just means brushing a positive wire on the post marked A. This puts current through the "pole shoes" (field) and re-established a magnetic field which the generator needs. You should get a little spark on the A terminal when you brush the wire against it. If you don't get the spark, try grounding the F terminal and then brush the wire against the A terminal again.

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