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Engine flush a motorbike

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Hi 

Ive a 90's cbr1000f, given to me from my dad, and no one can remember when it last got serviced. Guessing 5 + years, but its prob done less than 5000 miles in that time. Im going to drop the oil tomorrow, would you use a flush additive or straight up swap the oil. I use it regularly in my cars as i change oil regularly so i dont build up sludge, but im guessing in this it will be thick, am i better off not dislodging carp as it might affect the gearbox as well? 

Thanks

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I've never flushed any of my bikes previously and not had any issues.....I'd drain the oil and see what state it's in, if it's good just swap it and the filter etc. If it's nasty I'd do as PS has said above,put a cheaper oil in it and give it a run etc then swap with a better quality oil.

Years ago there were issues with some engine flushes perishing mineral washers etc it's probably been sorted now with modern flushes but not worth it if it does not need it.

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Ok ill just chuck some cheap oil in, do 15 mins up the road and drop it again. 

Gonna try and keep this sweet, its 1990 and only got 25000 miles on it. 

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It isn't the dry in your garage, not by engine standards - our relative humidity in this country is over 60% on average. A little less on very cold days. You think your garage is 'dry', but the air in it still contains moisture and it condenses out as the engine cools, so as soon as you turn the engine off (5 years ago) the moisture was already present and the hot air surrounding and within the engine held more moisture than the cooler air around it. Warm air can hold more water vapour than cold air. I would drop the old oil straight off - cold. It has already drained into the sump pan, so you only need to get it to run out of the hole in the bottom. Refill and use that as sacrificial oil.

Fire her up with the plugs out first. Just have a fresh battery and spin her over in short bursts, so you don't overheat the starter motor. Plugs out makes it easier to spin the motor with no load on it, to get the oil pump running and recharge all the galleries with oil, even the old oil is better than no oil. Then put the plugs back in and refuel (fresh fuel), just get her warm, a few minutes at 1200rpm should be enough. Don't blip the throttle, it won't be good for an engine that has been standing idle for long enough for all the oil to drain out of the bearing surfaces....let her idle fast enough to put the charging light out, certainly less than 1500rpm.

If you take her up the road be awre that the brake pads might shed their lining... so be careful I lost the linings out of my front pads once, going down the steep hill into Bath.... engine braking and the rear drum saved me! The pads just disintegrated. The tyres might also have gone hard, or even started to crack - so don't go hooning up the road. Go very steady, you are only loosening things up.

Don't be surprised if the fork seals also let go - an easy and cheap fix. I would change the fork oil too (SAE10 or hydraulic clutch fluid/autobox fluid).

The only flush it needs is to use some standard 10-40, probably needs API grade SF or SG at a guess. Silkolene, Putoline, Motul, Rock 10-40 will be fine. You don't want to use a car type oil - wet clutch doesn't like the additives used in seperate gearbox engines! Beemers and Guzzis you can use car oil because they have seperate gearboxes with their own oil - UJMs use the same oil for gearbox, clutch and engine.

Get her HOT on the new oil. Really hot, proper running hot. Then drop the oil and change the filter this time round. Don't forget the air cleaner - K&Ns? get some K&N oil and give them a proper clean and reoil.

Check the carb inlet rubbers - they are also likely to have gone hard and are prone to splitting after long periods of layup.

What is the chain like? While the engine is warming up, spray some chain lube on - main stand on a plank of wood (1/2" plank) to increase height, rear wheel off the deck (weight front or prop rear? Does she sit on front of rear when on main stand?) If she sits on the front wheel on the main stand all good. Just check the clearance under the rear tyre. Cable tie or just tie the front brake on - just in case! Tie lever to handgrip. Let her idle in bottom gear... rear wheel rotates and you can spray the lube on the INSIDE of the chain where it meets the sprocket on the lower run. The chain will carry the lube into the chain links.

ENJOY!

Edited by Accuspell

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On 22/02/2019 at 23:24, Accuspell said:

If you take her up the road be awre that the brake pads might shed their lining... so be careful I lost the linings out of my front pads once, going down the steep hill into Bath....

Which hill was that mate? Not from of the ones down from Lansdown was it? Bet that gave you a fright

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That  list is for my  exact model the 1000FM what is the letter after the F to identify  yours.

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On 24/02/2019 at 18:31, Budice said:

Which hill was that mate? Not from of the ones down from Lansdown was it? Bet that gave you a fright

Coming from south, got traffic lights at the bottom, before you get to the river/canal.

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6 hours ago, Accuspell said:

Coming from south, got traffic lights at the bottom, before you get to the river/canal.

Sounds like Limpley Stoke then on the A36

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Change the brake fluid, probably more important than the engine oil, I would strip and replace seals and pistons before you go blatting it round the streets getting the oil good and hot

Edited by Vince Green

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