SuzukiSavage.com - Strange start issue

stanabay

YaBB Newbies

Offline

SuzukiSavage.com
Rocks!

Posts: 24

Strange start issue
04/24/23 at 08:09:46

Hi
I have an 87 savage I have rebuilt over the winter, rockers, cam , gaskets, etc.
I put it together and it fired right up.
Needed carb tuning..no problem.
Rode about 5km in small test rides, all good just running rough because of wrong jets.
Start it up one day, ride down to the gas station to put air in the tyres, turn it off to fill gas, and now it won't start.
It was "whirring" while trying to start, like the starter had broken a gear. Bugger.
Trailer her home.
Decomp was not attached.Now it is.

Now the juicy part

With decomp attached I get 2 or 3 thuds, like a normal start up noise, then back to whirring. Bugger. But good sign the starter gears are OK? Opened head inspection port, things moving while trying to start. Good.

So now I take an extra sparkplug I have that I know is good, attach to lead and watch for spark while I crank.

I ONLY HAVE SPARK WHILE THE DECOMP VALVE IS OPEN. Decomp disengage and back to whirring and no spark.

disconnecting decomp no spark at all.

Battery is charged and hooked up to car with jumper leads, no change.

All safety switches are gone.

Any ideas guys?

I'm at a brick wall

Back to top

IP Logged

verslagen1

YaBB Moderator
ModSquad

Offline

Where there's a
will, I want to be
in it.

Posts: 28890
L.A. California
Gender: male

Re: Strange start issue
Reply #1 - 04/24/23 at 18:18:27

stanabay wrote on 04/24/23 at 08:09:46:

Start it up one day, ride down to the gas station to put air in the tyres, turn it off to fill gas, and now it won't start.
It was "whirring" while trying to start, like the starter had broken a gear. Bugger.
Trailer her home.

you might have a couple of broken teeth in your starter gear that just somehow lines up right to get you started.

to check, remove the starter and use your finger to spin the gears.

you should only be able to go one way, if you can go both ways then you found the broken tooth.

Back to top

Versey's Place
Tech Section Index

IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #2 - 04/25/23 at 06:52:29 Have not removed starter yet. I found this though, could this be causing this strange spark issue? Startor has seen better days also
Back to top	20230425_154838.jpg IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #3 - 04/25/23 at 06:54:40 I didn't change this on the rebuild due to them costing way to much. Have ordered a used one now. Is this the culprit?
Back to top	20230129_155407.jpg IP Logged

verslagen1 YaBB Moderator ModSquad Offline Where there's a will, I want to be in it. Posts: 28890 L.A. California Gender:	Re: Strange start issue Reply #4 - 04/25/23 at 07:57:48 those would could cause strange charging issues
Back to top	Versey's Place Tech Section Index IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #5 - 04/26/23 at 07:31:50 Anything else i should look at while I wait for my new stator? Anyone?
Back to top	IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #6 - 04/26/23 at 07:38:02 Theory im running with now, is i think I read somewhere that the decompression thing controls spark while its "on" When it's "off" the job gets passed to the stator and ignition pickup, which on my bike don't look to good. Theory sound?
Back to top	IP Logged

verslagen1

YaBB Moderator
ModSquad

Offline

Where there's a
will, I want to be
in it.

Posts: 28890
L.A. California
Gender: male

Re: Strange start issue
Reply #7 - 04/26/23 at 07:52:56

stanabay wrote on 04/26/23 at 07:38:02:

Theory im running with now, is i think I read somewhere that the decompression thing controls spark while its "on"

When it's "off" the job gets passed to the stator and ignition pickup, which on my bike don't look to good.

Theory sound?

don't think so.
the TCI has a lead to the starter and retards timing while starting.
the decomp is only active for a half second... not long enough to get it started.

Back to top

Versey's Place
Tech Section Index

IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #8 - 04/26/23 at 10:57:59 Quote: don't think so. the TCI has a lead to the starter and retards timing while starting. the decomp is only active for a half second... not long enough to get it started. heres where i got my theory http://suzukisavage.com/cgi-bin/YaBB.pl?num=1262917566
Back to top	« Last Edit: 04/26/23 at 18:48:33 by verslagen1 » IP Logged

verslagen1 YaBB Moderator ModSquad Offline Where there's a will, I want to be in it. Posts: 28890 L.A. California Gender:	Re: Strange start issue Reply #9 - 04/26/23 at 18:51:51 so it's the fuses fault, did you replace the fuses?
Back to top	Versey's Place Tech Section Index IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #10 - 04/26/23 at 22:01:59 Yep
Back to top	IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #11 - 05/21/23 at 06:43:28 so finally got some time to look at the bike. Starter spins both ways. Im confused how this will give me spark while the decomp valve is engaged but not after. anybody can explain it to me?
Back to top	IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #12 - 05/21/23 at 06:44:17 btw i replaced the startor, no change
Back to top	IP Logged

verslagen1

YaBB Moderator
ModSquad

Offline

Where there's a
will, I want to be
in it.

Posts: 28890
L.A. California
Gender: male

Re: Strange start issue
Reply #13 - 05/21/23 at 08:01:26

stanabay wrote on 05/21/23 at 06:43:28:

Starter spins both ways.

sorry, I might not have been clear. The starter will be able to turn both ways by hand, but the gears that it engages with will not. Remove the starter, put your finger in the hole it came out of and turn the gear. As there is quite a bit of reduction, it will take some time to turn the gear completely around. What you are looking for is a spot where the gear can turn both ways.
Quote:

Im confused how this will give me spark while the decomp valve is engaged but not after.

This maybe a clue. 1st, the decomp should only be active for half a second. Shortly before the starter engages and deactivated shortly after, max 1 or 2 revolutions. Sparky fires every compression and exhaust stroke, so you're seeing maybe 4 sparks and no more?

Ok, next rabbit hole. Sparky fires when the mag field in the coil collapses. So maybe a bad wire?

And are you sure your "whirring" sound is not a clicking sound?

Back to top

Versey's Place
Tech Section Index

IP Logged

stanabay YaBB Newbies Offline SuzukiSavage.com Rocks! Posts: 24	Re: Strange start issue Reply #14 - 05/21/23 at 10:14:37 Yeah, i push start button, decomp opens, I have spark and "standard" starting noise thump thump, decomp closes, no spark and whirring from starter.
Back to top	IP Logged