This is in regards to a 1992 16v k100rs.

This is most noticeable while on a hill, thanks to gravity. Anyways, while stopped at idle, with the front brake applied, if I rev the bike mildly quickly up to around 3k, the brake lever will actually push itself out and stick there for a second before actually allowing me to pull it back in. The brakes release and everything. It's very odd. The same thing happens when I have the rear brake applied. The brake pedal will essentially push itself back up, release the brake, and stick there for a second before allowing me to push it back down.

If I rev it *slowly* up all the way to 7k-ish, the brakes remain unaffected.

I feel that this could be related to the ABS, but that is functioning normally as far as I can tell.

Any ideas?

I cant say for certain about he K but I had the same behaviour on a 2000 Mercedes E Class which did have ABS and Brake Assist.

But the K does not have a servo the way a car does so it may not be the same. Does everything else behave normally?

92KK

Yep, everything else on the bike behaves normally (finally!)

I'm guessing the rapid change in battery voltage from idle is affecting the ABS brake modulators.

Basic2 wrote:I'm guessing the rapid change in battery voltage from idle is affecting the ABS brake modulators.

This would be the only thing I could come up with, maybe an email to Tosi Tabuki the ABS genius in Japan, he may be able to shed some light on it. Like you say it sure is a strange one, maybe its possesed and I don't mean by a finance company.

Funny now that you mention battery voltage I recall this was much less noticeable after I replaced the battery.......

Some other issues arose and the suggestion was to run a diagnostic check at €75 plus VAT but that it was likely to be the battery. I spent the money on a battery instead.

Battery is brand new too! .

Well, if / when I figure this out, I'll post back and let you all know.

That is an interesting phenomenon I guess the first questions that form in my mind are have all connections to and from the ABS been treated with DeoxIT to rule out any odd connection issues. Next what is the battery voltage at idle and how does that rise when you open the throttle so as to eliminate any weird voltage fluctuations from the diagnosis. If the alternator/regulator electronics/regulator brushes/slip rings have a problem you could be getting strange voltages out. Use an accurate fast DVM to do the check.

I would read out any fault codes stored as well just to see if anything is stored there once you have done that do a CPU reset and see if the problem is still there and read the fault codes again.

Last quick check after all the above is get a friend to swap their ABS CPU into your bike does the problem go away? If it does that would indicate to me that the problem is CPU related having already eliminated all connection and voltage issues.

Let us know what you find.

Regards,
K-BIKE