I'm a newbie

[oldnslo]

Hello out there--I'm new to this forum, but have been riding for quite a few years, have been primarily a sportbike rider for the past 8 years. A few months ago, I discovered that an aging body [62] loses some flexibility over time and my formerly comfortable Honda CBR1100XX was getting to be a literal pain. As in back pain. Tried the usual fixes, nothing worked so sold it, bought an xj900rk with 4700 miles on ebay and it will probably be my last ride unless I come into some money. Only thing that concerns me is if the valves need frequent checking and re-shimming or do they pretty much stay in spec unless one spends a lot of time red-lining the engine. The owners manual specifies valve check at 3000 miles and every 5000 therafter. I think the shim system is the same for all xj valvetrains, so somebody may have some experience to share. Every 5000 seems a bit often to me. Even screw and lock nut adjusters go further between checks and adjustments.

[mitch]

valve adj

now bear in mind im not right in saying this but my xj has 44000 klms on it and the valves have never been shimed. it runs very quite no valve noise so you can do what u like im leaving mine alone lol just my opinion ,doug

[TopCatGr58]

Welcome to the Forum,

I got my 81XS11 in '83 with 15 miles on it, rode it for 9 years, some estimated 40+kmiles, never had the shims checked or adjusted. They don't wear that easily and with proper oil changes and such, they should stay within spec for years. The advice is to set them to the wider larger spec, you would think that as the shim/cam lobes wear that the clearance would increase, but other thoughts state that the valves slightly receed into the valve seat over time putting the valve actually closer to the lobe!?!? Also, allowance for heat expansion, the clearance will close, and if set too close, could lead to slightly open or not fully seated valves during operating temps, possibly leading to burning valves!?!? Happy riding!

T.C.

[oldnslo]

Thanks, T.C., what you say matches what I've heard about shimmed valves. I wish the manual wasn't so paranoid about it though. 5000 mile intervals seems ridiculous. My Blackbird was good for 16000 in the manual, and most riders ran 40k + or never checked them. I will have to check them, I just can't help myself. If they are within spec I probably won't bother again.