The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: suecanada on August 09, 2007, 07:25:45 PM
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Well, guys, I attended Oaks tech. seminar on Airheads at the national and he had Joe katz with him, another grand dealer/guru from way back. Joe travels from rally to rally last time I talked with him and he starts out in Florida in April. Anyway, LRB will be getting a valve job done by Bruno here in canada. Oak was saying that a BMW airhead can be generally counted on the keep running well with regular maintenance of fluids etc for 80,000 miles...After 80,000 miles one can expect to have to do bigger jobs like valves and other more major things.
Is there a school of thought that says when ya get the valves done you should put in new gaskets and O-rings everywhere on the cylinders?? I do know I should put in new pushrod seals and I have one pushrod seal that is very rusty so i guess I should get that replaced too.I ask this as I am wondering if I would be wise to leave the entire motorcycle with Bruno so he can do things that would be wise to do or maybe I am better to do everything other than the valve work. Dilemma time...what did Rob do???? In my heart of hearts I don't want to leave LRB with Bruno for the winter..he says he is booked up until November. Once the bike is up in Iron Bridge at that time of year there is no going and getting it until May at the earliest. I am a worrying Mother!
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Sue, heaven forbid anyone confuse me with any sort of "expert" here, because I don't even pretend to be one, but I've learned the hard way a few times that giving a vehicle to a mechanic to just "do whatever it takes" can usually lead to a staggering repair bill! Not to accuse anyone of anything at all dishonest, but your ideas of "in good shape" and their ideas of "just like new!" can easily conflict, bigtime. Do you really want to invest $4000 into a $3000 bike, for example?
Obviously, much of the expense involves labor costs, and if you're gonna be in one area already it often makes economic sense to have other parts replaced while everything's apart, especially if you intend to keep the machine. Still, though, I'd request, demand, an itemized estimate and some sort of guarantee of a cost ceiling: if more repairs are found, everything stops until you give the go-ahead. Once all those shiny new parts are in there, they ain't gonna take them back out for free. If a competent, honest mechanic won't work under those restrictions, I'd walk away.
Sorry, but I'm always the "realist", as some who've accused me of pessimism have later declared.
Otherwise, good luck! [smiley=thumbsup.gif]
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Sue, first of all, don't go by what this Rob would do! I have no idea until the action is happening.
To begin, I have heard that all of the pieces of the valve train should be kept segregated from their kin to keep mated parts together.
I believe you mean one of your pushrod tubes is rusting?
If so, while the heads are off being done, either replace the one (most folk [I gather] do all 4) or all 4. They make stainless ones. If you want Bruno to do that work for you, you will need to leave the cylinders with him, also.
Yes, replace the two small o-rings on the top two studs, and the large thin o-ring that goes around the base of the barrel.
I usually replace the head gasket at least every-other time I have the head off. If it has been a while, I replace it anyway. I just use the stock part.
When you remove the cylinder, put something under the piston/con-rod to support it, resting on the lower studs.
Use a magnet-on-a-stick and pull out your cam followers. They have been known to crack or flake.
Put them back if they are O.K.
That is about it for what I did.
I have been told I should have had the cylinders honed (I don't have your Nikasil) and possibly new rings while I had it apart. That constitutes a "true" top-end job, I guess (I don't know...).
Let's see what others say.
And no, I would not drop the bike off.
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Sue, if you have the heads off, replace the cylinder base o-rings and the push rod tube seals regardless how good they look. I would suggest a complete overhaul of the carbs, if nothing has been done to them in recent memory. I did mine about 2 months ago, and I was amazed at how worn the needle jet , as well as the throttle shaft o-rings, and the 'choke' o-rings. My transmission was making a low frequency 'rumble' and it turned out to be the bearings were damaged by water (rust). Also it is possible that the clutch is close to replacement time as well. My bike is just shy of 80,000 miles, and this is what I found, the maintenance gets a little expensive at 80,000 miles. My brake rotors were worn beyond in service limits, so you may want to check that as well. At last count, this last maintenance cycle cost me $2000 US. I've yet to get the bike running, as my work schedule, and this unrelenting desert heat has not allowed me time to get the bike back on the road ! Hopefully at the end of September the temps will get back down to a reasonable level to continue what work needs to be done yet.
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Hi Sue,
When I got my top end done the following things were done at the same time:
1) New head gaskets.
2) All new o-rings.
3) Replaced the small end bushings on the connecting rods.
4) Replaced the con-rod big end bearings.
5) Two of the four lifters were showing wear and were replaced.
6) The rings on the push rod tubes were tap welded in the proper place so they wouldn't slide up the tube and starts leaks at the big seals at the bottom end of the push rod and the crank case plus fresh seals.
7) Cam chain and guides/tensioner were replaced.
8) New rings and cylinders honed (1980 - cast iron sleeves not nikasil).
On my to do list is Carb Diaphrams and needle jets and the needles themselves. It is amazing what effect on mileage worn needles and needle jets have on our carburated bikes.
My bike carries more than the typical R65 hence the replaced bearings and bushings. I doubt you have as much wear on your bike as I did on mine unless you drive at 90 mph everywhere all the time! :D
Hey Rob - Did you mean "Valve-Lifters" instead of followers? I didn't think our bikes had followers like the Ducatis do??
TTFN,
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If you still have the original brake lines, might be a good time to replace them as well. How old are the throttle and clutch cables ? I replace mine at about 25,000 miles, unless they start binding up earlier. How old is the ignition coil, and ignition leads? Have the alternator brushes ever been looked at ? Do a cleaning, inspection, and lube on the starter, I guarantee it needs lubrication. How about shock absorbers, are they OEM or replacement shocks ?