Bandit Alley
GENERAL MOTORCYCLE FORUMS => GENERAL MOTORCYCLE => Topic started by: rmtcook on March 04, 2007, 10:56:59 PM
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I hope this isn't a dumb question, but with a little more than 100 Miles on the bike I'm hearing a fairly obvious tapping when at idle. I assume it's valve tap, but should I get it checked out or is it normal on the Bandit or is it just cause it's still so damn cold here? :thanks:
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Its when the tappets are not prancing that you should worry. (Correction to my last) The valve will slowly wear its way into the engine, taking up clearance until the valve is held open and burns. This is almost always the case and the primary concern, hence no sound and the valves start to burn unable to close and you start back firing, then its too late. Being a little loose is not going to hurt but remind you that there is clearance. If you happen to install a jet kit early, that would be a good opportunity to pull the valve cover and check/adjust the tappets to the proper clearance cold and check them 3 times before buttoning up the job. Otherwise just wait for the scheduled maintenance period but don't expect the dealer to do a real check. 99% only make money when they let your bike sit for a day and call you thats its ready, so do it your self and learn something new.
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As cam wear occurs the valve clearance gets tighter and tighter until there is no more tolerance or clearance
Huh?
Uhh... cam wear would create looser tolerances, not tighter. And wear usually occurs on the followers, tappets, or valve stem caps much sooner than it would on the cam lobes.
The only things that would cause valve tolerances to get tighter would be the valves seating during initial break-in, or the valve seat surfaces eroding or "cupping" from prolonged heat.
I hope this isn't a dumb question, but with a little more than 100 Miles on the bike I'm hearing a fairly obvious tapping when at idle. I assume it's valve tap, but should I get it checked out or is it normal on the Bandit or is it just cause it's still so damn cold here?
Make sure your oil level is good. Sometimes a fresh engine will use up a bit during the first few miles.
A little tapping is normal as the valve train "settles in" during initial break-in. It may get a bit quieter as the valves seat. The older Bandits have adjustable rockers, so they tend to be a bit noisier than the newer "shim-and-bucket" design.
They will be a little louder at colder temperatures. It should get quieter as the engine operating temperature rises. I'd just keep an "ear" on it for the next few hundred miles. If it's still getting louder by the time your first oil change is due, I'd suggest having an expert listen to it. (Not necessarily the dealership mechanic... :roll: )
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It is completely normal on the air/oil cooled Bandits for them to have valve noise, even when warmed up. If they're quiet, you need to adjust them!
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In all my years of motorcycles, I have never seen a valve get lose from wear. I have seen the lock nut on the adjuster screws come lose and back off the adjustment.
Valves get tight because of valve cuping. The thin outer edge will cup, causing the valve to set deeper in the head, causing the valve to have no gap on the adjustment.
If a cam wears enough to let the valve get lose, you have a bigger problem. :beers:
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I haven't seen it on bikes either... but I have seen them get looser on car engines with mechanical adjustment.
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On small block chevys, I have seem them pull the stud out of the head. Back in the 60's and 70's, I built some wicked small blocks, and I always ran solid lifters. I liked the Z28's 30/30 cam, because you could really hear the lifters.
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I've seen valve tolerances get looser from wear on cars and bikes both. Usually it's either the follower surface (where the rocker rides on the cam lobe) due to insufficient lubrication, or the valve stem cap can flatten slightly due to loose tolerances.
The adjusters can develop some flattening also, where they meet the valve stem cap. The threads can get loose. The rocker can develop looseness at the pivot shaft. And of course, cam lobe wear.
Most of these problems are caused from insufficient lubrication, or improper adjustment. As BHolland said, it would mean you have bigger problems, most likely lack of proper oil delivery.
The initial statement that cam lobe wear causes tighter tolerances is false, and I noticed has now been corrected. (you're welcome, BTW) I pointed it out as to avoid Rmtcook getting false information.
Also the cupping wear described is a result of heat and erosion over time, as I stated. It does cause tighter tolerances, as I stated. I never disputed that tight tolerances cause burnt valves, that's common knowledge. When a valve doesn't close, combusted gas escapes under compression and burns the valve, usually the exhaust valves go first.
Here's a good place to learn the basics: http://www.bandit-heaven.co.uk/public_html/valve_adjustment.htm
Valve train wear is not as common a problem these days, but I've seen my share of Nortons, Triumphs, and other older twins with adjustable rockers having such afflictions as described. Modern metallurgic developments have reduced these problems to a minimum, but the nature of the design is prone to wear.
All moving parts will wear eventually. :wink:
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I've had this discussion before and it has been my experience that valves get looser as they wear.
But agree that a little loose is better than a little tight.
Actually I have never found a tight valve on the many thousands that i have checked and adjusted.
mine were loose at 1,000km. and were adjusted. checked again at 13,000km. and they haven't changed a bit.
the most wear does happen in the first few kilometers. once the parts wear down any high spots adjustments are needed infrequently.
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The cams turn at 1/2 the speed of the engine, where does all the wear come from.
I have been building, and racing motorcycles for fourty years, I will be 60 in July, and my experience is that valves loose the gap, but it doesn't make any difference when you adjust them, as long as they are right when you get though. :motorsmile:
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The cams turn at 1/2 the speed of the engine, where does all the wear come from.
Half of 10,000 rpm is still 5,000 rpm. :wink:
I have been building, and racing motorcycles for fourty years, I will be 60 in July, and my experience is that valves loose the gap
Forty years and you've never seen a worn valve train component? :shock:
Maybe that's because race builders, especially drag racers such as yourself tear down and rebuild their engines so much more frequently, before they have a chance to wear. I'd say you'd see a lot more catastrophic failures on the racetrack than you would loose tolerances. (Unless you're a poor old roadracer like me who just ran 'em till they wore out. :roll: )
I'm not trying to be a smartass, BH, I'm just trying to point out how our experiences could differ... I have 5-gallon buckets full of worn cams, rockers, adjusters, and other worn parts from over a few decades of wrenching. If you walk into my shop I can pull them out and show them to you.
28 years, ASE certified (9 certs) professional auto repair, and owner, builder, rider and racer of dozens of motorcycles during my lifetime (in my 50's) including many, many friends bikes.
but it doesn't make any difference when you adjust them, as long as they are right when you get though. :motorsmile:
Agreed. :beers:
If they're quiet, they're probably too tight, and you need to adjust them before they burn. If they're noisy, they're loose. Not as urgent, but you still need to adjust them eventually.
The point is you gotta adjust the valves regularly, otherwise why did they put adjusters on them? :roll: :grin:
As far as cam lobe wear, whether it's common or not, it would cause looser tolerances, not tighter. And friction causes wear, period. (Unless maybe it's two diamonds rubbing together... in which case, you could afford to hire your own live-in master mechanic... :banana: )
:motorsmile: :bigok:
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I'm hearing a fairly obvious tapping when at idle
Some good info here. But a couple of things about your basic question.
1. If you have a loud "TACK", sounding like a single tappet, then you should get it checked. You may have an adjuster that came loose. Unlikely, but not impossible.
2. If you are hearing a VERY mild "ticking" or "clatter" sounding like a number of tappets, that is louder when it is cold, and gets quieter (but does not disappear) when warm, then yes, that is normal.
You should get all the valves checked at the first major service, 1000 km (600 miles).
I have checked mine a few times now. Never much of a change, but this last time (35,000 kms) I had 2 tight and 2 loose out of the 16. All still within spec, (+/- 0.001") just at opposite ends. I normally set them right in the middle. The 2 tight ones were on the exhaust side, the 2 loose ones on the intake.
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That's always been my experience....:roll:
In all my years of motorcycles, I have never seen a valve get lose from wear. I have seen the lock nut on the adjuster screws come lose and back off the adjustment.
Valves get tight because of valve cuping. The thin outer edge will cup, causing the valve to set deeper in the head, causing the valve to have no gap on the adjustment.
If a cam wears enough to let the valve get lose, you have a bigger problem. :beers:
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not saying you're wrong just stating my experience, I'm only 57
i do however agrree that no ticking on a B12 is a bad thing.
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The wealth of information on this board never ceases to amaze me! Thanks one and all for your feedback. As a non-mechanic, what I'm taking from this is that a fair amount of clacking is normal, what I'm hearing on my bike doesn't rise to the level that would warrant concern, so I'll at least ask that the shop check the valves at my first service. Thanks for the help!! :thanks: :motorsmile: :beers:
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You're welcome!
If anything, all this feedback proves it wasn't a dumb question after all, aye? :wink:
I think this was the best direct answer to your question:
1. If you have a loud "TACK", sounding like a single tappet, then you should get it checked. You may have an adjuster that came loose. Unlikely, but not impossible.
2. If you are hearing a VERY mild "ticking" or "clatter" sounding like a number of tappets, that is louder when it is cold, and gets quieter (but does not disappear) when warm, then yes, that is normal.
Sums it up pretty good, I think. :bigok:
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Yep, Zenman, pmackie pretty much nailed it.
Another caution though:
YOUR OIL LEVEL SHOULD NEVER BE LOWER THAN 1/3 THE WAY DOWN THE WINDOW WHEN CHECKING IT COLD !!!
.....ESPECIALLY DURING BREAKIN !!!
....BUT EVEN ANY TIME AFTER BREAKIN, AS WELL !!!
This may seem like simple stuff to you pros.....but a lot of newbies (to bikes in general) think they can run a bike like a car i.e. near/at the add mark. REALLY BAD IDEA !!!!
I won't go into the long boring reasons why you need to do this (which you pros already know) but for the newbies......
KEEP THE OIL AT OR VERY NEAR THE FULL MARK......
and, yes, that means carrying a bottle of your favourite lube with you any time you're going to be away from home for at least one night.
As my dear old dad (a journeyman mechanic for over 40 years) used to say: YOUR time and oil are cheaper than SHOP time and parts. :wink:
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Bucket shims are better! Good to see the site back up! :stickpoke: :stickpoke: :stickpoke: :monkeymoon: :wink:
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Iv never looked forward to removing the cam to get under the bucket to mic and replace those darn small shims. Although I will admit the time between having to make an adjustment is longer. On my DRZ400 its 15000 miles. Above bucket is easier requiring only a tool to remove/replace the shim.
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LOL - Screw & locknut was an item that swayed me to the Bandit - price didn't hurt any either.
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I suppose I should know this but what valve adjustment system does the Busa use?
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Shims in a bucket atop of valves. Very involved deal. Most that use synthetic oil never have to have em done. The zuky schedule says not needed to 18k miles and then most aren't out of tolerance. :beers:
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You havn't lived until you have done the valves on a ZX 12, it is almost eaiser to remove the engine than to do it in the bike. :duh:
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He he... here we have two different "valve philosophies"... interesting! :grin:
Personally, the shim & bucket design was something I loved about the old Kawi inline 4's... to me it's so much easier to just measure your clearances, calculate the difference from the old shim, then pop in the new one. They hardly ever needed changing, and you didn't have to mess with the whole locknut/adjuster deal.
Less moving parts, stronger, longer time between adjusments... another reason I like the new B1250 too.
It's all good, each to their own, right? It's always good to have different schools of thought, otherwise we couldn't have all these fun little debates! :bigok:
:beers: :motorsmile:
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Bandit cost to adj ZIP! Not even a cover gasket if your careful! Bucket type when they need done %$#%$%^$#%$ $175.00 kit and that is the cheap one. Most zuki shops don't have em all. The H Busa.org was going to start a bank of sorts so the little pills could be swapped for others not needed. To do an adjustment on a Bandit an afternoon, to adj a Busa! Days of planning, a weekend if your good, and most likely another week to get the parts in to complete the job. Or you could take it to the stealer which they will scratch it up, screw it up, make your bike sit for a week and then lie and say they did the job! I had a Kawi LTD 1000 that i rode for 38k miles when it started making some noise. Paid a shop to do the shims. I went to pick it up after it was done. My secrete mark on the valve cover was not moved at all! But they swore they did em and they were way out. They put STP in the oil so it sounded better until it thinned out! I went back and almost got arrested but they had another shop check em while i was there. They never touched em but the mechanic that knew his stuff said buy a Kerker 4-2-1 mag and ride it like you stole it! I did and sold it to a local @ 44k... I saw it at the local drag strip during bike week the other week end. Its turning low 10's !!! :duh:
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I have done 2 or 3 Busas, and a whole bunch of ZX12s. I have a hundred or so of the shims, and the motorcycle shops around here have always traded me shim for shim.
The most time comsuming thing is dialing the cams back in when using adjustable cam sprockets. Of course, the rocker/screw type is eaiser. The FJ 12 and ZX 11, you could change shims without removing the cams. :beers:
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Yep, you tend to collect a good shim collection, and the shops are usually willing to trade.
The shim-on-top design is the easiest, with the special tool you could depress the bucket and slip the shim in and out in a couple seconds. :motorsmile:
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The above bucket shims on my old CSR 750 were pretty strait forward to remove with the depressor tool, mic and order from the dealer. Under bucket shims are suppose to be much safer as above bucket shims have been known to tiddlywink out of one bucket from under the cam during high RPM and land under another cam causing all sorts of funny sounds and problems followed by rapid deceleration.
:grin:
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yep the "normal" valve adjustment on the B12 is one of the reasons i chose it.
Older hondas were great in that they had a port hole of sorts over each valve so that you did not need to remove the whole valve cover to adjust the valves.
Kawasaki ZR7S is a real pain to add shims. i dont mind adusting mine on the B12 at the beginning of each season.
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Its when the tappets are not prancing that you should worry. (Correction to my last) The valve will slowly wear its way into the engine, taking up clearance until the valve is held open and burns. This is almost always the case and the primary concern, hence no sound and the valves start to burn unable to close and you start back firing, then its too late. Being a little loose is not going to hurt but remind you that there is clearance. If you happen to install a jet kit early, that would be a good opportunity to pull the valve cover and check/adjust the tappets to the proper clearance cold and check them 3 times before buttoning up the job. Otherwise just wait for the scheduled maintenance period but don't expect the dealer to do a real check. 99% only make money when they let your bike sit for a day and call you thats its ready, so do it your self and learn something new.
Might as well ask a wise man this question: Is there a dial-gauge setup available for Bandit valve adjustment? If so, where?
Thanks, Herb
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Might as well ask a wise man this question: Is there a dial-gauge setup available for Bandit valve adjustment? If so, where? Thanks, Herb
Sure if you pull the engine! Bandit easy to do but still cramped on room. Why? Just more moving parts to make a misstake with. :beers: :bigok: Oh i C you said wise man! Not a wise ASS. Sorry :duh: :roll:
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I'm afraid I am not that wise, There is no mention of use for one in my manual (Clymer) in measuring valve adjustment until you start measuring the camshaft itself for run-out. There is use for one on my DRZ400 if under bucket shims are needed at 15K since the camshaft must be removed :crybaby: . I am not looking forward to buying that tool or using it twice before I die.
Might as well ask a wise man this question: Is there a dial-gauge setup available for Bandit valve adjustment? If so, where?
Thanks, Herb