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petesmeats
4th April 2006, 12:47
My 87 CBR 600 Jumps out of second... Pretty dodgy in some situations.
My gear changes are also getting noisier and noisier and clunkyer and clunkyer.
I did an oil and filter change when i first got the bike and it made it better for a while but is definately getting worse now.
How do i fix this?
I am a little strapped for cash being a poor uni student.
How much would this cost?
Cheers

vifferman
4th April 2006, 12:56
Firstly, make sure tyour chain and sprockets are in good condition, and that your chain is clean, well-lubed, and properly adjusted. This makes a HUGE difference to gearchanges.

Secondly, if the cush rubbers in the rear hub are tired (which they likely are, then changing these (about $30 bux?) or padding them with rubber to take up some of the slack can help.

If your gearbox (specifically your shifter dogs and drums) are 'ted, then you're up for $$$$. Too much for a "poor uni student". Honda boxes, particularly high-mileage and/or thrashed ones are notorious for this kind of behaviour. Fitting a shifter kit when the 'box is still good helps this, but it's too late now.
Sorry...

madboy
4th April 2006, 12:57
Find a finance company that charges massive interest - they'll lend you enough money to trade on a brand new one.

miSTa
4th April 2006, 14:49
Secondly, if the cush rubbers in the rear hub are tired (which they likely are, then changing these (about $30 bux?) or padding them with rubber to take up some of the slack can help.

As for $30, I wouldn't think so. I enquired about the same thing for the 1100 late last year - $130. Needless to say I packed it with an old inner tube. Otherwise +1 on what vifferman had to

Jonty
4th April 2006, 15:22
Jumping out of second is unusual. CBR's do not have the world's quietest gearbox as my 98 is not silky smooth. Take it in for a mechanic to have a squizz and they will put a cost on it for you fairly qucikly.

XTC
4th April 2006, 15:34
I would say worn gearbox internals.... Bike is 19yrs old now. Can be repaired but unless you could do it yourself you're possibly looking at 2K plus.... Maybe try to find a goodish 2nd hand motor.

petesmeats
4th April 2006, 16:01
Its got a new chain on it. The adjustment is ok. It has a new front sprocket on it with + 1 tooth and the rear sprocket seems ok. I will Lube it up again just to see if that makes a difference and will check those cush rubbers. Hopefully my bike is not totally ****ed but if it is how much would i be looking at paying for a second hand engine and do any later model engines bolt in?

F5 Dave
5th April 2006, 14:05
Does it jump out just after you put it in, or anytime?

This may sound silly but if your gear lever is at a funny angle -like fairly high -you may simply just not be regularly lifting your foot high enough or it may rub against the case slightly to prevent full travel. Make sure the lever bites onto the spline tight.

It can help as a technique to load the lever with your foot, not touch the clutch & cut the throttle; once the load is removed it will change.

The change from 1-2nd is the longest physically as the shift star has to travel over the neutral position. Esp if the lever is rubbing against something.

Sometimes a weak detent spring (which rides the wheel on the star) will exacerbate the problem. Replacing this spring Ďmayí help.

Else itís split the engine time, or at least the bottom end, which may not be that hard.
If there is damage to the gears then the places to look are the engaging fingers that mesh into the slots of the gears. Little bit rounded or angled? The problem is this damage will tend to push the gear back out rather than engaging.

These can be undercut so the gears pull together, however care is required to avoid pulling them so they move too close. Also the shift dogs may be bent so they donít mesh far enough in.

petesmeats
6th April 2006, 09:07
OK Last night i had a play and i cleaned and oiled the chain, Re-tensioned it and it has made a marked difference. How often is it recommended that one cleans and oils the chain? Also in my Manual (Clymers) It says that my left fork takes 371cc of oil and my right takes 361cc. Why is this? is it just a weight distribution thing or are the left and right forks different somehow?

F5 Dave
6th April 2006, 09:17
Different. My CBX & RG had antidive in one side. Best measurement is a measurement from the top compressed with no springs. That way they are equal height.

petesmeats
6th April 2006, 09:25
Yeah thats the way that i did it... The other thing that im wanting to do is to get a centre stand for my bike cos its pretty ****ing annoying having to string it up anytime i want to do work on it. Is it possible to do this for my bike ('87 FH)? or do i have to get a race stand?

riffer
6th April 2006, 19:08
A race stand is probably the cheaper option.

aff-man
6th April 2006, 19:58
I had the same problem with my 98 cbr600f3

Work second gear and bearings were to blame...

Got it replaced and it worked a treat

James Deuce
6th April 2006, 20:48
OK Last night i had a play and i cleaned and oiled the chain, Re-tensioned it and it has made a marked difference. How often is it recommended that one cleans and oils the chain? Also in my Manual (Clymers) It says that my left fork takes 371cc of oil and my right takes 361cc. Why is this? is it just a weight distribution thing or are the left and right forks different somehow?

Chain should be lubed every 600kms or so, wipe the excess off. Clean it when it needs it. Lube it more frequently if you ride in the rain. Always adjust chain tension to the tightest point on the chain.

Anti-dive in the left fork leg is why it requires more oil in the left. It's a hydraulically activated, and now thoroughly extinct 1980s fad.

GR81
6th April 2006, 20:55
Chain should be lubed every 600kms or so, wipe the excess off. Clean it when it needs it. Lube it more frequently if you ride in the rain.
how often should one remove the chain and soak it in kerosine or whatnot?
or is simply giving it a good lube enough?

F5 Dave
7th April 2006, 08:36
With toothbrush & kero you can get it pretty clean in about 5min, but usually lube is fine. Watch out if there is a noticeable tight spot it may be end of days for that setup.

Obviously if you do have a stand it makes it easier, but never run the bike to oil/clean the chain. Too many people have munched fingers.