Author Topic: What's that CLACK when she turns over but wont start?  (Read 12395 times)

0 Members and 1 Guest are viewing this topic.

2bikebill

  • Grand Gearhead
  • *****
  • Posts: 1,877
  • Karma: 0
  • ~ it's about the ride ~
After 4000 happy and troublefree miles my G5 has recently begun a strange and disconcerting behavior when starting. It's not every time, but occasionally, instead of starting on the button, it'll turn over in an irregular sort of way with a loud metal to metal CLACK instead of firing up. It feels and sounds like something in there has just got stuck in the wrong position. Switching off and trying again generally cures it and away she goes. Sometimes I kick it over slowly first.
This is definitely a bike not suffering from neglect or thrashing and is ridden pretty much every day. Regular servicing, oil changes etc.
This symptom kind of rings a bell from an earlier post which I can't find, so any clues welcome.
Thanks.
Will
2009 Royal Enfield Electra (G5)


clubman

  • Grease Monkey
  • ****
  • Posts: 300
  • Karma: 0
Reply #1 on: July 06, 2010, 08:57:23 am
I don't have an answer Will but, incredibly enough, at 3,700 mine started doing exactly the same. Just the last few times it's been starting first time again. The CLACK seems to be from the starter motor area but realistically could be anywhere. For sure it's from the engine area and is a mechanical CLACK, and not a starter motor relay click. Naturally when I mentioned it to my dealer it behaved perfectly.  ::)


r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2,986
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Reply #2 on: July 06, 2010, 01:08:38 pm
Could it be the decompressor flyweight?
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association


ace.cafe

  • Grand Gearhead
  • *****
  • Posts: 14,457
  • Karma: 1
  • World leaders in performance/racing Bullets
Reply #3 on: July 06, 2010, 01:16:39 pm
Could it be the decompressor flyweight?

That was my first thought too.
Auto-decompressor noise.
Home of the Fireball 535 !


ES-335

  • Scooter
  • **
  • Posts: 22
  • Karma: 0
Reply #4 on: July 06, 2010, 02:01:32 pm
I am afraid it might be the decompressor if clacking on the right side of  the motor. I have had that part replaced twice, first time the flyweight "hinge" was broken, managed to drive home that time. Taken to service. The second time the cam lifter pin of the decompressor got loose and fortunately ended at the bottom of the engine (that´s what the mechanic explained to me). This incident misfired the engine at speed of 90 km/h and blasted the airfilter box lid open, also lid lock broken. Had to push the RE closer to home, though engine a bit later started again and ran for some 10 kilometers. Then the engine stopped when revs close to idling at traffic lights, started no more. Another 1,5 km push to home. In total 2 trips on a tow truck to nearest RE service (50 kms away). Now there is no auto decompressor installed at all.
« Last Edit: July 06, 2010, 05:27:59 pm by ES-335 »


2bikebill

  • Grand Gearhead
  • *****
  • Posts: 1,877
  • Karma: 0
  • ~ it's about the ride ~
Reply #5 on: July 06, 2010, 03:59:03 pm
Well that all sounds more than a bit alarming. And since it's happened three times more today I think perhaps I'll get on the phone to the dealership.
And Clubman, it's spookier than you think. I should've said almost 4000 miles - I'm actually at 3900, but this first started a couple of hundred miles ago (cue Twilight Zone theme tune.... :o )
So if the bike runs without the auto decompressor fitted - what's it for..?  ???
2009 Royal Enfield Electra (G5)


Ragmas

  • Grease Monkey
  • ****
  • Posts: 358
  • Karma: 0
Reply #6 on: July 06, 2010, 04:12:08 pm
It is for starting the bike.  A big 500cc trying to turn over in full compression  might be a bit difficult on the foot, if using kicker.  I don't know how this hurts the starter motor if at all. 

I would imagine that this is why the non-efi bikes have a decompressor lever, for starting.

Sam
2009 G-5 Military
Little Falls, NY


2bikebill

  • Grand Gearhead
  • *****
  • Posts: 1,877
  • Karma: 0
  • ~ it's about the ride ~
Reply #7 on: July 06, 2010, 04:37:44 pm
Thanks Sam. Assuming it has no effect on the electric starter, might as well ditch it then, if it comes to that.
2009 Royal Enfield Electra (G5)


SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Reply #8 on: July 06, 2010, 04:57:44 pm
In my case it was the sprag which unfortunately I had to change it three times by now.


ES-335

  • Scooter
  • **
  • Posts: 22
  • Karma: 0
Reply #9 on: July 06, 2010, 05:19:30 pm
My C5 had these decompressor failures at around 4700 and 5300 kms (2900 and 3300 miles). The RE importer in Finland explained me that the autodecompressor was aimed exactly to Indian C5 (and other) models that have both estart and kickstart. In order to ease kickstarting. It was also told that RE UK informed the Finnish importer that the auto decompressor could be left out regarding RE models without kickstart. That was the recommendation after that 2nd case. So far I have not sensed that full cylinder pressure would be a burden for that electric start. Now my RE has thumped about 1000 kms (620 miles) without decompressor.
« Last Edit: July 06, 2010, 05:31:05 pm by ES-335 »


Ice

  • Hypercafienated
  • Grand Gearhead
  • *****
  • Posts: 6,753
  • Karma: 0
  • Ride In Paradise Cabo, Don and Ernie
Reply #10 on: July 06, 2010, 05:27:33 pm
In my case it was the sprag which unfortunately I had to change it three times by now.

Is yours a UCE powered machine or one of the older models ?
No matter where you go, there, you are.


SSR

  • Grease Monkey
  • ****
  • Posts: 280
  • Karma: 0
Reply #11 on: July 06, 2010, 05:36:12 pm
Is yours a UCE powered machine or one of the older models ?

Its UCE C5.


r80rt

  • C5 Pilot
  • Grand Gearhead
  • *****
  • Posts: 2,986
  • Karma: 0
  • R.I.P Papa Juan, Uncle Ernie
Reply #12 on: July 06, 2010, 05:42:29 pm
Thanks Sam. Assuming it has no effect on the electric starter, might as well ditch it then, if it comes to that.
It lifts the exhaust valve momentarily, and makes life easier on the starter and sprag.
« Last Edit: July 06, 2010, 05:46:18 pm by r80rt »
On the eighth day God created the C5, and it was better looking than anything on the planet.
Iron Butt Association


2bikebill

  • Grand Gearhead
  • *****
  • Posts: 1,877
  • Karma: 0
  • ~ it's about the ride ~
Reply #13 on: July 11, 2010, 01:11:58 pm
So is this  wheeze - CLACK, wheeze - CLACK  more likely to be the auto decompressor or the sprag? (a word I have heard but don't fully understand)

It's happening more and more, and embarrassed the hell out of me yesterday when I tried to get off the Dartmouth ferry!  I thought it wasn't going to start at all, but persistence paid off in the end.

 I'd like a theory in place before I take it in to the dealer because I know they're new to Royal Enfields, and probably haven't come across this   -  yet.

4200 miles otherwise trouble-free.
2009 Royal Enfield Electra (G5)


ace.cafe

  • Grand Gearhead
  • *****
  • Posts: 14,457
  • Karma: 1
  • World leaders in performance/racing Bullets
Reply #14 on: July 11, 2010, 01:37:36 pm
So is this  wheeze - CLACK, wheeze - CLACK  more likely to be the auto decompressor or the sprag? (a word I have heard but don't fully understand)

It's happening more and more, and embarrassed the hell out of me yesterday when I tried to get off the Dartmouth ferry!  I thought it wasn't going to start at all, but persistence paid off in the end.

 I'd like a theory in place before I take it in to the dealer because I know they're new to Royal Enfields, and probably haven't come across this   -  yet.

4200 miles otherwise trouble-free.

Yes, more likely to be the auto-decompressor. That's a sound that a decompressor would make.

The sprag is simply one of the gears in the electric starter system, which is a one-way gear like a ratchet, which the starter turns when starting.
It has parts inside the sprag gear, called a sprag clutch, and this is what makes it work in one direction only.
If something happens to make the bike kick back, it can break the sprag clutch mechanism, which was a common occurrence on the older models which had electric starters.

It is my view that the auto-decompressor also helps to protect the sprag clutch from breakage, by letting the engine begin to spin-up and get some forward momentum, before the auto-decompressor releases at the specified rpm point, and then the engine starts.
By removing the auto-decompressor, you do raise the risk of damage to the sprag clutch by a kickback. It's simply a matter of solving one problem, but leaving yourself open to another problem occurring later.

The ideal circumstance would be to fix the auto-decompressor so that it works properly, and the system will function as intended, and the sprag clutch will be more protected from damage.
Home of the Fireball 535 !