+1 with Kev on checking those pipes,my A model suffered the same symptoms, compression was 125psi on all 3, My left cylinder exhaust was totally blocked,fitted Delkevic's to fix the problemcanaletto5 wrote:Also worth checking the exhaust pipes aren't clogged with carbon.
1974 GT 750 loss of power
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- Location: Sydney NSW Australia
Re: 1974 GT 750 loss of power
Cheers.
Roger
GT750A.
Roger
GT750A.
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- Posts: 19
- Joined: Wed Jan 10, 2018 6:41 pm
- Location: gatwick
Re: 1974 GT 750 loss of power
Update. Upon further inspection, there is no spark to the centre plug, looking at it again, the plug still looks brand new! I have swapped plug caps and plugs around, and they work on L & R. So I presume it’s the centre coil? The coils seem to be powered from the regulator, which, as the other 2 coils are working, must be ok? I also swapped the condensers around, no joy! So maybe a new set of coils?..
Martyn
Martyn
- canaletto5
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- Location: Derbyshire
Re: 1974 GT 750 loss of power
Hi Martyn
Individual coils can fail. It may be the HT lead needs replacing. If it is a beige coloured coil then the lead can be unscrewed after removing the gungy seal around it. You can then screw a new length of HT lead in. If it is a grey coil then it is a bu*ger to repair. Then it may be worth getting a replacement coil. Kev
Individual coils can fail. It may be the HT lead needs replacing. If it is a beige coloured coil then the lead can be unscrewed after removing the gungy seal around it. You can then screw a new length of HT lead in. If it is a grey coil then it is a bu*ger to repair. Then it may be worth getting a replacement coil. Kev
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- Posts: 3693
- Joined: Wed Jul 20, 2011 3:40 am
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Re: 1974 GT 750 loss of power
How is the timing,have you disturbed the points in any way,wiring etc,
Cheers.
Roger
GT750A.
Roger
GT750A.
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- Posts: 19
- Joined: Wed Jan 10, 2018 6:41 pm
- Location: gatwick
Re: 1974 GT 750 loss of power
Thanks guys, checked the timing manually, points seem to open when they should. I tried to unscrew the HT lead from the offending coil, but it wouldn’t budge, just stretched a lot! There is definitely power getting to the coils, so looks like ebay for a replacement.
Thanks again for your help and suggestions chaps
Thanks again for your help and suggestions chaps
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- Posts: 19
- Joined: Wed Jan 10, 2018 6:41 pm
- Location: gatwick
Re: 1974 GT 750 loss of power
Update 2..The problem is fixed .. I bought a set of used coils from eBay, Bingo.. either it was the centre coil or HT lead was breaking down, so whichever it was, has sorted the bike, it flies along now. Happy boy.. Thanks again chaps for getting me on the right path.. Brilliant..
Cheers all
Martyn.
Cheers all
Martyn.
- canaletto5
- Posts: 5228
- Joined: Tue Jul 23, 2013 8:43 pm
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Re: 1974 GT 750 loss of power
Nice one