Compression test part 2 - results not good!

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Morespeedvicar
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Re: Compression test part 2 - results not good!

Post by Morespeedvicar »

Wat about a faulty valve stem seal? The only way your going to find out wats going on is top up the oil so you know exactly were it is, go for a ride (ignore the smoke) then look at the level the next day when the engines cold again! If the levels gone down alot and there isnt a pudle on the floor( or in the belly pan) it must be burning it! Are all the plugs the same color? Doing compression tests is fine, but remember that these are tiny little engines and even using a long pipe from the plug adapter to the gauge can make a differance!
My FZR smokes loads untill it get hot but doesnt use oil or water, its just condensing the water vapour in the exhaust pipe when its cold.
If its playing up alot look at shim clearances for a start and wont take long to do.
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Cammo
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Re: Compression test part 2 - results not good!

Post by Cammo »

Morespeedvicar wrote:My FZR smokes loads untill it get hot but doesnt use oil or water, its just condensing the water vapour in the exhaust pipe when its cold.
My nc30 does this also.
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viper61
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Re: Compression test part 2 - results not good!

Post by viper61 »

Did you say you're using a plastic washer inbeween the adaptor and spark plug holes? Have you tried with an o-ring? Need to fully seal the gap ideally.
oldgreyandslow
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Re: Compression test part 2 - results not good!

Post by oldgreyandslow »

viper61 wrote:Did you say you're using a plastic washer inbeween the adaptor and spark plug holes? Have you tried with an o-ring? Need to fully seal the gap ideally.
Yes it's why I tested #3 again and they're all around the 8 bar dry and around 11 with the addition of oil, so the general consensus of opinion now seems to be clean the carb's again, check float heights (forgot to do that last time) jets back to standard, fresh fuel, oil, antifreeze and see what happens. Get it well warmed up and keep an eye on the oil levels.

At least that's the plan for now
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viper61
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Re: Compression test part 2 - results not good!

Post by viper61 »

Yep a slight difference but not tragic. I would do what you've said, check valve clearances while you're at it (if not done already) then after the carbs are all cleaned, put those on (make sure they're fully sealed on each rubber inlet - a bit awkward at first but patience and they'll go on no prob). I think you can warm the rubber manifolds up before hand (hair dryer) which will make them more flexible and easier to attach the carbs. I just bought some new ones last time, as they were in need of replacing.

Then give the carbs a balance (again, patience is needed) then once all that's done you're good to go.

Hope it all goes well.
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Re: Compression test part 2 - results not good!

Post by porndoguk »

stick your carb rubbers in petrol then go jelly soft and make putting them on SUPER easy, i use put a bit of grease round the lip
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oldgreyandslow
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Re: Compression test part 2 - results not good!

Post by oldgreyandslow »

porndoguk wrote:stick your carb rubbers in petrol then go jelly soft and make putting them on SUPER easy, i use put a bit of grease round the lip
Plan is now to clean float needle valves and filter, check float heights, the gaugue you sorted arrived today btw (damaged envelope looked like some bugger opened it to see what was in there!) give it all one last blast of cleaner, soak rubbers overnight and try to fit it all back when I get home from work tomorrow.

Hadn't thought about balancing carbs, do I need a vacuum gauge balancer (carbtune)? If so I do wish I'd not sold mine when I got rid of the Fazer a few years ago! If its anything like that one it's a complete bastard to adjust, and how the hell do you get to the adjusters and run the engine if the tanks off. I know, get the Haynes out!

Fresh fuel, quick prayer to the Gods of bike starting, probably fire it up with the standard can still attached, warm it up, bleed cooling system, leave to cool, go grab a beer.............

Then decide what to do about can, put plastics back on and ride the bloody wheels off!
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Drunkn Munky
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Re: Compression test part 2 - results not good!

Post by Drunkn Munky »

I never bother with vacume gauges, you can get it close enough using the drill bit method. i think theres a thread in the workshop section somewhere but you basically use a drill bit to set the butterflys all the same with the carbs off then adjust the idle with the bike running.
oldgreyandslow
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Re: Compression test part 2 - results not good!

Post by oldgreyandslow »

Drunkn Munky wrote:I never bother with vacume gauges, you can get it close enough using the drill bit method. i think theres a thread in the workshop section somewhere but you basically use a drill bit to set the butterflys all the same with the carbs off then adjust the idle with the bike running.
Great, thanks, I'll get searching
oldgreyandslow
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Re: Compression test part 2 - results not good!

Post by oldgreyandslow »

oldgreyandslow wrote:
Drunkn Munky wrote:I never bother with vacume gauges, you can get it close enough using the drill bit method. i think theres a thread in the workshop section somewhere but you basically use a drill bit to set the butterflys all the same with the carbs off then adjust the idle with the bike running.
Great, thanks, I'll get searching
I've searched carb balancing + drill bit method and drill bit method + carb balancing, all good stuff but a bit confusing nobody actually explains what bits you adjust however it does sound as though it's covered by Haynes too, I'll go and look there, in the meantime if there is a "How to" thread with pic's somewhere and someone knows where it is, please post a link. From what I could see it may be on the "old" site................

Lazy, me?

Ta

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