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Hey Guys,

I have an old 1989 mc19. I noticed that when i applied the brakes with some force that the back end of the bike seems to lock up and I can hear the back break skipping like its loose or something.. But the callipers feel sturdy to touch.
Also, when moving, Im often getting stuck between gears.. bike just free rolls and then clicks back into gear by itself after a big jolt. and it can be hard to find neutral sometimes. Wondering if this is due to having an old sprocket or can I just lube the parts?


And one last thing, Any tips on washing/degreasing the engine on these old beasts? Dont want to get water past the seals etc.... because last time I drenched the bike a bit much and had to replace some plugs etc.

Thanks for your time and sorry for the noob questions

Corey.
 

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Look at the sprockets (front & back) to see if the teeth are curved looking (like a wave) instead of nice straight points - this will mean it's worn out.
Also check your chain slack as per the manual, it may be too loose and jumping off the sprockets?

Use degreaser and a brush then turps and rags?
Shouldn't need a high pressure hose.
 
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I have been told never to use high pressure water on a sports bike or a cruiser, as you said the water gets past the seals and causes problems. if you aren't keen on spraying degreaser, e.g. near chains or other parts that are supposed to be lubed, you could spray it on a cloth and then wipe the cloth on to the parts you want to clean, then attack them with an old tooth brush or other suitable scrubbing brush.

Regarding your rear brakes, remember that when you brake the weight from you and the bike is lifted off the rear tyre and on to the front, which is why the rear brake is always easier to lock up. Also, unless your clutch is in while you brake, your engine is turning the sprockets and forcing the rear wheel to rotate even when you apply brakes, which may account for your locking and skipping of the rear brake.
 

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If you want to clean the chain properly, get yourself a chain brush (such as here) and just scrub it with SAE 90 gear oil (fortunately both of these are cheap as). The brush will mechanically clean all the gunk off, and the oil will work into the bearings without too much excess.

You'll hear a lot of differing opinions about chain cleaning, but the service manual is very specific about not using spray-on chain lube and only using SAE 90.

As for the gearbox; has the oil/filter been changed recently? If not (or using shite oil) that can affect the gear selection. Additionally, does it have difficulty finding neutral when the engine is off or on? A huge amount of these bikes have clutches that never properly disengage, which means they have a tendency to skip over neutral while idling.
 
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