Starter motor groaning on hot start

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redhot
Posts: 15
Joined: Sun Jun 22, 2014 8:39 am
Location: Sunshine Coast, QLD, Australia

Starter motor groaning on hot start

Post by redhot »

I have a strange groaning noise coming from the starter motor on hot start only. The motor still turns the engine over (reluctantly) and it starts OK. It sounds like it is struggling with an additional load. This has happened after my local mechanic (who is very experienced and builds race engines) fitted Krieger manual CCTs. I also seem to be getting a larger amount of engine vibration. My mechanic had a listen and said the sprag clutch was on the way out, which is a bit unlucky as the bike has only done 27k klms. I’ve just done 4500 klms over 7 days on a big outback ride and it’s no worse, but boy do I have bad carpal tunnel syndrome from the vibes. I haven’t ridden this far before on the VTR, so I don’t have anything to compare it with. Any thoughts on the starter noise? Could this and the bad vibes be related to the adjustment of the manual CCTs or is it coincidence?
tony.mon
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Location: Norf Kent

Re: Starter motor groaning on hot start

Post by tony.mon »

There's an easy check, wind both manual tensioners out two flats and see if the noise lessens or disappears. That's not enough to cause any possibility of damage.
If it's not that, it probably isn't the sprag clutch, although I have spares if you need one, it will be the two transfer gears, which are locked together but can start to move one against the other if you are unlucky.

See my thread in Workshop Knowledgebase- it's not a monster to repair, but don't use the Honda method, I have a better one.
It's not falling off, it's an upgrade opportunity.
redhot
Posts: 15
Joined: Sun Jun 22, 2014 8:39 am
Location: Sunshine Coast, QLD, Australia

Re: Starter motor groaning on hot start

Post by redhot »

Thanks for the words of wisdom Tony. I'll check out your ideas.
macca__macca
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Joined: Mon Mar 31, 2014 4:21 am

Re: Starter motor groaning on hot start

Post by macca__macca »

Redhot, I just had my mechanic install Krieger manuals and have exactly the same problem! The mechanic says it's the starter clutch but it can't be coincidence and the fact that we both experience the problem straight after manuals were installed confirms it.

Where did you get to with fixing this issue?
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VTRDark
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Joined: Sun Mar 18, 2012 9:24 pm

Re: Starter motor groaning on hot start

Post by VTRDark »

Over-tightened tensioners. Get a new mechanic or better still do it yourself. At leas you know it's done right then. :roll:

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macca__macca
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Joined: Mon Mar 31, 2014 4:21 am

Re: Starter motor groaning on hot start

Post by macca__macca »

Awesome thanks, hopefully that's exactly the problem with mine too. Were you able to loosen the tensioners without having to remove the tank and airbox or does it all have to come out?
macca__macca
Posts: 56
Joined: Mon Mar 31, 2014 4:21 am

Re: Starter motor groaning on hot start

Post by macca__macca »

Also hoe much did you loosen them? Half a turn? Or did you have the engine running and loosen them while it was running? I've never done it before hence the questions!
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VTRDark
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Re: Starter motor groaning on hot start

Post by VTRDark »

There's various ways of checking/loosening them. The safest and surest way is to strip things down and measure.
Manual Cam Chain Tensioner Installation Guide (MCCT's)

Otherwise without the engine running, (preferably with the piston at TDC on the compression stroke) loosen the lock nut on the tensioners and slowly unwind the tensioners by 1/4 to 1/2 turn out and see if things improve. The front tensioner is awkward to get to so you will most likely want to remove the tank and airbox.

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macca__macca
Posts: 56
Joined: Mon Mar 31, 2014 4:21 am

Re: Starter motor groaning on hot start

Post by macca__macca »

Took it back to the shop and had them adjust the tensioners when the bike was properly hot. They had to loosen one of the tensioners less than 1/4 of a turn and the hot start noise is apparently gone. I pick it up next week so time will tell!
tony.mon
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Joined: Wed Jul 25, 2007 10:46 pm
Location: Norf Kent

Re: Starter motor groaning on hot start

Post by tony.mon »

Don't give that bunch of cowboys any more of your money. Incompetence costs engines.... :whatever
It's not falling off, it's an upgrade opportunity.
macca__macca
Posts: 56
Joined: Mon Mar 31, 2014 4:21 am

Re: Starter motor groaning on hot start

Post by macca__macca »

Yep, loosening that tiny amount fixed the groan on hot start. The bike now holds idle better than it ever has, too, so I definitely had an air leak, which the service manual does call out as a probable cause of trouble holding idle.
Geordie
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Location: Ayrshire

Re: Starter motor groaning on hot start

Post by Geordie »

Totally agree with Tony. So many of the hot start problems we hear about on this forum are simply because the manual tensioners are too tight.. the engine block and head will expand with heat causing the chain to tighten.. This is one reason why automatic tensioners are fitted.. It is a far more delicate job to adjust these than is often mooted on here. I had exactly the same issues nearly burnt out the stated motor nevermind the excess wear to camshaft bearings etc. I'm afraid unless your mechanic has specific experience on firestorm manual tensioners then he's as much in the dark than most of us before we fitted manuals ourselves! I locked off my old tensioners and measured the exact distance they were locked at from edge of rubber boot to the mounting flange (56.5mm iirc) and adjusted the manuals and locked them at that before installing them. I found that was too tight and had to back them off three flats if I recall. I'm always listening for changes in tone from the engine top end in.casevthey are needing more adjustment but it's very difficult to differentiate when the blinking thing is so loud lol..
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