| Author | Message | ||
     Rays |
At the last service of my '06 Uly (64,000km) I discovered that the interactive exhaust valve was firmly stuck in the closed position. I regularly do the cycle test on this valve but have been doing that by listening for the servo to operate. Unfortunately it appears that there is some form of clutch in this servo (if not something slips when the valve is stuck) and it makes all the right noises but with the valve firmly in the closed position. After a lot of fiddling about (that valve is in a very awkward spot with the muffler still on the bike), I found that if the valve pulley was lifted slightly with a screwdriver being used as a lever (approximately .020"), the valve could then be opened. Problem was when the valve was allowed to return to the closed position it would drop down slightly and get stuck again. I eventually adjusted the cable such that the valve was held open slightly and couldn't return to the closed position. I did try wiring the valve completely open but for my particular tastes it had too much of a negative impact on the 'feel' of riding it. I persisted with the valve held slightly open until the next service (68,000km - yes I probably do over-service it but it is still running beautifully) but that mode of operation makes the Uly feel 'off'. So with the chin spoiler and tank cover off for the 68K service I thought I would have another stab at this. The only solution (short of getting the damn muffler cut open or laying out some $$ for another muffler) seemed to be getting a spacer under the pulley valve without jamming it completely. It is in a very difficult spot to measure the end-play but with some experimentation with various wire thicknesses I came up with between .025-.028". In order to gain access to the gap beneath the pulley the valve needs to be in the full-open position. This simple arrangement will hold the valve open without any damage to the cable:  I tried putting a normal 'E' circlip in there but with the limited access I gave up and eventually tried this:  This is .026" thick and was a little tight but after exercising the valve a dozen times or so it settled in quite nicely. The valve can now be allowed to snap shut with no hint of jamming. I assume that the bottom pivot inside the muffler must eventually wear to the point where something starts to catch - not having seen the thing first-hand I can only guess at that. Anyway the end result is that my interactive exhaust valve is back to working as it used to. The exhaust is much quieter when this valve closes completely and it might be the placebo effect of getting this solved but I am convinced that the low-speed manners have been restored. This might be a completely isolated incident but probably worth checking for those of you with more 'senior' Ulys that still have the standard muffler. |
