I have just done the service and shim check on my S4 . 2 years ago I had to replace all the opener rockers as 5 were knackered at only 5000 miles ,I reckon the previous Japanese owner must have been very hamfisted . i fitted Megacyle rockers from Nichols in USA . Now 2 years and 7500 miles later they are all still perfect as are the closers ..I only had to replace 2 closer shims and 2 opener shims .
I always gently warm the bike up so oil gets up to the heads and rockers before revving the motor above 1500 rpm.oil is changed every 3500 miles.
the M750 rockers are still perfect at 16,000 miles no problems at all.
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MONSTERMAN
That's some good news there! :)
Quote from: jerryz on March 12, 2009, 08:39:19 AM
I reckon the previous Japanese owner must have been very hamfisted .
I wouldn't make that assumption.....I bought my 748 brand new, and at 5600 miles, I replaced four rockers. The gaps were HUGE. I had a couple that were over 0.20mm, so apparently the rockers were beat to death. I wound up changing 13 out of 16 shims. At 12k miles, most tolerances were the exact same as I had left them, and others were no more than 0.001" different, so I didn't change a single shim, plus, none of the rockers looked any different than 6k miles previously.....and I wasn't very easy on that bike in those 6k miles between services, so.......your bike could have been like mine, and left the factory with some overly large clearances that beat the chrome on the rockers. I am in the process of doing the 18k, but I haven't pulled any cams, yet....hoping to be motivated this weekend and do at least the horizontal cylinder head.
Quote from: jerryz on March 12, 2009, 08:39:19 AMthe M750 rockers are still perfect at 16,000 miles no problems at all.
You rarely hear of any issues with 2V rockers. My ST2 looked terrific at 36k miles, and I dog the cr@p out of that bike.
I've only seen two 2V rockers that had chrome issues....EVER. I kept one just so when people say,'That's a 4 valve problem', I can prove them wrong... [laugh]
As opposed to dozens of 4V rockers.
Glad to know your problem seems to have been sorted and that the valve adjustment went well!!!
Quote from: jerryz on March 12, 2009, 08:39:19 AM
i fitted Megacyle rockers from Nichols in USA .
I'm in the process of looking for a good deal on some Megacycled rockers. I finally pulled the horizontal cams out of my 748 this past weekend.....I guess I know where a large portion of my tax refunds is going.
This is one of the OEM replacements that I installed in 2006 (they were $45 each, back then). This rocker looked fine after 6000 miles, but somewhere between 6k and 12k, it decided it was allergic to its chrome....
(http://i32.photobucket.com/albums/d32/Kramer_Krazy/bad_2006_rocker.jpg)
I recently bought an S4. It has just over 12,000 miles. When the valves go out of adjustment, do they generally get tight or loose? As for the rockers flaking, do you just start hearing more noise, or do you notice stuff in the oil filter and oil, or just when you take a look see in there do you see it?
Thanks, Robert
you will see chrome flakes in the filter , noise is about the same , some get looser usually .