My Barn Twins

Discussion in 'Airheads' started by fxray, Feb 26, 2015.

  1. Werner1111

    Werner1111 Adventurer

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    Ray - I've been enjoying your thread for awhile. I'm on the tail end of rebuilding a 1978 R100/7 and just went down this path. I thought about saying something when you reached the point of setting the end float on the cam (I had to go back and pull mine out, too), but didn't want to discourage you and was hoping you would find a better way!

    I just thought I'd jump in at this point since I do have a resource for those clips and many other metric fasteners at http://www.mrmetric.com/ and here is a link to the e-clip - http://www.mrmetric.com/metric-fasteners/metric-e-rings-steel-m2-3/

    I have no relationship with Mr. Metric other than satisfied and repeat customer. You can buy single fasteners from them and the prices are great. Shipping is a flat $6 for USPS priority on orders up to $50 and free above. I've made quite a few orders to them as I've been doing my restoration.

    I hope this helps you and others out.

    Keep up the great thread. This is fun to watch!
  2. fxray

    fxray Long timer

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    Thanks, Werner, and good luck with your project. It's always good to know another source for parts like this. I still can't believe they don't throw in a few extra clips with those chains, when they are so little cost, but the bean counters are in charge. I can't be the only ham fisted person doing this. In my search, I was also looking for the one-piece fish clips for the master links. There are some available, but they all look eerily like the one that got written up here.

    When I backtracked and removed the e-clip that I had put on successfully, it was actually fairly difficult. I hope that difficult-to-remove-on-purpose translates to stays-put-in-operation.

    Ray
  3. bpeckm

    bpeckm Grin! Supporter

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    Who knew! That is indeed a very cool tool, so simple and elegant in its simplicity. Circlips and their brethren are always a beeyitch to deal with, spread it just-enough, and don't let it go boing.



    I think we-who-hangout-here are all tool whores to some extent, but ..... I think you're nominated for the Obscure-Tool Order of the Year!!



    :jack
  4. fxray

    fxray Long timer

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    A little progress for a change, some good news, and a tool review:

    McMaster-Carr, being the excellent supply house that they are, delivered my stuff quickly (see post #120 a page or so back). I now have a man-size supply of those e-clips, meaning I can lose them, break them, whatever, and still carry on.

    [​IMG]

    The good news is that the tool works so well, I don't need all those extra clips! Here's some pictures for those who are not familiar with one of these e-clip applicator tools. The way these are normally used, the supply of e-clips is loaded on a mandrel, and there is a little platform such that you can slide the tip of the tool across the surface and quickly load a clip into the tool jaws. For this limited job, needle nose pliers work just fine.

    [​IMG]

    The tips of the jaws are shaped to match the e-clip. If you were using a variety of e-clip sizes, you would need a tool for each size. Note the end of the tool has a shelf or counterbore in each jaw. Looking at the picture above, you can see that I loaded the clip with the lip or shelf down. The picture below shows the lip or shelf a little closer:

    [​IMG]

    With the clip loaded, the spring steel jaws are spread a little to grip the sides of the clip. Here, I have turned the tool over:

    [​IMG]

    The lip is helping keep the e-clip straight in the jaws::

    [​IMG]

    On the other side of the jaws, the surface of the e-clip is flush with the surface of the jaws. Because the tool is sized for these particular e-clips, the counterbore depth in the jaws matches the thickness of the e-clip:

    [​IMG]

    You want that flush side against the side plate on the master link. It is a good fit.

    Because the e-clips are stamped items, one side will tend to have a more sharp edge, while the other side will be more rounded. This is slight, but noticeable. The clip will tend to stay in place better if the sharper edge is facing away from the plate on the master link.

    Here, I had installed one clip and was ready to do the next one. These were for practice, for taking pictures, and for evaluating how well I think the clips will stay in place. I believe they will work just fine. They are actually difficult to remove:

    [​IMG]

    In much less time than it takes to tell about it, the job was done! Easy peasy! No pain or effort involved!

    [​IMG]

    [​IMG]

    My timing marks were lined up. They are rather hard to see with the chain on the sprocket, so I had put a splotch of white paint on them. A tooth on the crank sprocket lines up with a space on the cam sprocket.

    [​IMG]

    This while at OT on the flywheel, which is now back in place with the new single-use bolts from Bob's BMW.

    [​IMG]

    [​IMG]

    You can scroll up and see pictures I took showing the slack in each direction with the old chain and sprockets. It didn't look too bad to me -- hence all the indecision on whether or not to replace my parts. The new chain has much less slack and should last me as long as I own this beast. Note that the tensioner is not yet installed:

    [​IMG]

    [​IMG]

    The new tensioner went into place without any need to notch it on the backside. My old one was notched, and I have seen pictures on here where people found it necessary. I was glad to see that it fit as it was:

    [​IMG]

    So now maybe I can move this along a little bit. I think I'll feel better once I have the engine slotted back into the frame, which will be soon now. I have not as yet even unwrapped the frame to see how the new powder coat came out. That'll be like unwrapping a Christmas present to myself!
    bpeckm and Lornce like this.
  5. bpeckm

    bpeckm Grin! Supporter

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    Well done, and from someone who has fought a lot of those clips over the years, that toll is slick! And I do like the 2 vs. 1 aspect of using the circlips rather than the one-piece.

    A moot point of course, but do you have any feel for what the residual slack would have been with JUST a new chain, and not the new sprockets?


    :ear
  6. Pokie

    Pokie Just plain Pokie.

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    Wow, that's quite affordable, I need to order me some stuff from McMaster Carr!
  7. fxray

    fxray Long timer

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    bpeckm, in this case, I think it would have been about the same as shown. I didn't have a lot of sprocket wear. Some people say that if you only do the chain, the worn sprockets will be a mismatch and will wear out the new chain rapidly. Some say that the cam sprocket lasts twice as long as the crank sprocket because it only makes one rev for every two revs of the crank. In the end, I just didn't want to have to worry about it. I had the engine this far apart, so I just decided to go for it.

    If I ever get this bike on the road, I hope to put lots of miles on it.

    Ray
  8. fxray

    fxray Long timer

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    Update: :( I accomplished nothing on this airhead the past few days other than a couple or three screw-ups!

    When I got the cam chain and sprockets back together, I didn't have the proper wrench to torque the two bolts that hold the cam bracket to the front of the crankcase. I could have made something up, but I didn't want to cut up one wrench out of a set to do it. Hey, it's a German bike, so I just used German torque -- the ol' gutten-tite method!

    Here's what I mean:

    [​IMG]

    The 3/8" drive body on my 5mm allen wrench fouled the tach drive gear, so I couldn't use my torque wrench. I just used a regular L-shaped allen wrench and did what felt like 13-14 lb.ft. to the torque wrench in my wrist.

    Then I moved on. I want to get the timing cover back on the front of the engine. Once that's done, I plan to slot the engine back into the frame. Anticipating that, I unwrapped the frame to check out the powder coat job. It looks great.

    BUT -- I found a "Note to Self" stuck in with the timing cover. "Don't forget to install the tach drive parts before you put this cover back on," it said. (At my age, notes like this are useful.)

    That set me off on a 2 hour search for the new seal I had bought for the tach drive. I finally found it, right in plain sight where it should have been, and went to install it. I had a 10mm, 1/4" drive socket that was about the right size to be a seal driver. I stuck it on an extension, lubed the O.D. of the seal, and tapped it in with a little hammer -- crooked!

    An 11mm socket would have worked, but I didn't have one in 1/4" drive. There isn't room for my fatter O.D. 3/8" drive socket to fit into the bore in the timing cover. O.K., fine. I have destroyed the little seal, so it's time to quit. I went and placed an order for two more seals -- one to install, and one for backup in case I wreck another one. Hmm, I hate to pay shipping for just this, but I can't think of anything else I need right now.

    This began a search for a better seal driver. The little tach drive seal is 16mm O.D., which is slightly bigger than 5/8 inch. I couldn't find anything on hand that would work very well. What I needed was a piece of 5/8" O.D. tubing. So . . . this morning I was off to the Ace Hardware Store.

    They had some in CPVC, and the size was perfect!

    [​IMG]

    That's the original, old, brittle seal there in the picture. The new ones might be here by tomorrow. I'm all set with a driver.

    [​IMG]

    But wait, at Ace Hardware, I noticed they sell individual metric allen wrenches. I started having guilt feelings about the gutten-tite cam bracket bolts. I'll fix that!

    [​IMG]

    [​IMG]

    Great idea, except, as I sorta expected, I had over tightened the bolts by the gutten-tite method. The problem here is that these are steel bolts into aluminum alloy. The alloy has a higher rate of thermal expansion. As the engine heats up, the bolt stretch is likely to increase quite a bit. These are critical bolts. I don't even want to think about them failing!

    Of course, as I tried to loosen the bolts to re-torque them, I rounded out the socket head in one of them. It was too late to add them to the seal replacement order, so they will come separately -- more shipping! The good thing is, there seems to be a mistake -- these fancy little bolts only cost $.42 each. That's the cheapest BMW part I have seen yet. As the last of the big-time spenders, I ordered 4 of them to have some spares. Why not, gotta pay the shipping cost anyway you know!

    These bolts might be here the day after the seals get here. Then, if it all goes right, I can get that timing cover back on and proceed with the job.

    I spent the rest of the afternoon reading everything I could find on here about R90/6 piston rings. All things considered, I decided to go with BMW OEM. (I'm aware of the ring end-gap issue, and will have more to add on that later). I could have combined them with my bolts order, except . . . the rings are $133.82 from Bob's or Max BMW. They are $56.20 from Moto-bins for the same part number! So, you think, get the bolts you need from Moto-bins along with the piston rings and only pay the shipping to one place! Yeah, well, the bolt isn't in Moto-bins' system.

    Things can only get better. Meanwhile, to quote Peter Egan, "Life can't pass you by as long as there are Triumphs!" Our late December weather has been good enough for some really nice rides on the TR6!
    :beer
  9. mr jazzbo

    mr jazzbo Adventurer

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    Hi Ray,

    Glad to see your back at it. I figured once the weather got cooler you would be. Always looking forward to your progress.

    I re-read Julia's thread from stem to stern last month. After (only) six years (from disassembly) I figured it was time to put my 78 Tiger back together.
    Thanks again for the motivation and always good reading.

    Jim
  10. fxray

    fxray Long timer

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    Thanks, Jim. I almost feel like I owe you an apology if you went all the way through that thread, but I guess nobody forced you! :-) Good luck with your build.

    I'm always looking forward to my progress too, but it just doesn't happen very often. I did get enough for an update though.

    I was hoping to get the timing cover back on. The replacement seal for the tach drive arrived and I installed it O.K. this time. I figured the bolt for the cam bracket would be here the next day after the seal, but it didn't make it for almost a week. Turned out that although I only needed one bolt, I ordered four because they were cheap and I'd have some spares. Well, that's fine, but Bob's BMW held the order. They only had two on hand and they made a special order to get two more for me. So I have spares I may never use, and it held me up for a few days. :dirtdog My own fault!

    The cam bracket bolts did arrive and I torqued them to 156 lb.ins. (13 lb.ft.), so I can quit worrying. That let me put the timing cover back on. I had been worrying about that all week. I just knew that crank nose bearing would give me problems, but it actually was pretty easy.

    With all three seals (crank, cam, tach) in the cover, I heated the whole cover in the oven at 210°F for 15 minutes. I made sure the two upper "doughnut" gaskets were held in position with a dab of grease and the main gasket was in position on the crankcase. The cover dropped right into place. I quickly installed the three nuts and one bolt adjacent to the crank nose bearing and torqued them to 68 lb.ins. While the cover was cooling off, I lightly ran in the rest of the fasteners. In a few minutes the cover was cool enough to touch. I broke the fasteners loose and lightly tapped the cover left / right till it was centered on the points quill (here, I mean only moving it a few thousandths of an inch). This picture is from before I took it apart, but it shows the same thing:

    [​IMG]

    Then I torqued all the M6 fasteners to 68 lb.ins. and called it good.

    Last week, I had put the suction bell back in the sump with a new gasket and used a little Blue Loctite on the bolts. The pan went back on with a new gasket and newly cad plated bolts and washers. They all went to torque with no problem. I used Blue Loctite on those as well, except the one nearest the oil filter. It goes into a thru hole, so I gave it some thread sealant.

    That let me put the lump back into the frame, and I had a plan to rig the engine and main frame with my lift in such a way that it could live there till the whole build is nearly done. I think it is going to work just fine. The lump is not very heavy at this point, so it was easy to stick it into the frame.

    With the normal rear engine mounting stud slid through, and a slightly longer threaded rod in place of the front mounting stud, the engine was secure in the frame. Then I picked up the frame and engine together and set it on the lift. My wife dropped the bolts into place that I had laid out for her.

    [​IMG]

    With this setup, the frame is secured without any need for tie-down straps. I can raise or lower it easily to make it convenient for whatever part I need to access. It is about halfway raised here. I can also spin the whole rig around in a circle if need be, or just roll it to one side out of the way.

    There is easy access to the rear, including putting the wheel on when I'm ready. As the bike gets more complete, the lift has a stabilizer that can swing out fore and aft. One is visible here:

    [​IMG]

    Same in the front:

    [​IMG]

    Here's the way it is bracketed to the lift. The rear brackets go where the centerstand should be:

    [​IMG]

    [​IMG]

    I have had this lift for quite a while, but this is the first time I will have used it to hold the entire bike. Always before, it has made a very sturdy engine stand. I have quite a variety of brackets made up to adapt it in different ways.

    Triumph engine:

    [​IMG]

    This same R90/6 at teardown:

    [​IMG]

    Honda engine right side up:

    [​IMG]

    Or upside down with the cylinder studs still in place.

    [​IMG]

    It is a versatile tool for sure, and I prefer it to a bike table for a number of reasons.

    Once the bike is a roller, I will lower the bike down onto its wheels and get somebody to hold it while I unbolt and withdraw the lift and install the center stand. Who knows when that day might get here? Oh well, the build is starting to go clockwise, as the saying goes. :rayof

    Cheers, and Merry Christmas!

    Ray
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  11. bpeckm

    bpeckm Grin! Supporter

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    ...and a Merry Merry back at you and yours!

    As always, an inspiration to read your posts, and I thank you! Love seeing the lift in various modes... you are indeed "King of the Tool Stash" :-)
  12. fxray

    fxray Long timer

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    bpeckm, As I was messing with setting up my R90 to go onto the lift, I was reminded of your R90 conversion and your discussion about the oil filter clearance to the frame. When my bare engine was on the stand, I had put it there with some 1/2"-13 threaded rod run through the crankcase, both front and rear.

    [​IMG]

    [​IMG]

    This 1/2" diameter rod is a sloppy loose fit in the holes through the crankcase, and I was going to use it with the engine back in the frame (not permanently, only while the bike was in process on the lift). So, imagine my surprise to find that 1/2" rod is too large in diameter to go through the holes in the frame! What's up with this -- more fine German engineering? The original engine mounting studs are 12mm diameter, and fit nicely in the frame holes, but there is more than enough slop for adjustment where they pass through the crankcase. It's almost like there should be a bushing of some kind in there.

    I wound up buying a stick of 12mm threaded rod to pass through the front hole on the engine and frame. The original mounting stud was long enough to work, but just barely. Nobody like Menard's or Ace Hardware had 12mm threaded rod in stock. Fastenal had it for $34 for a 1m stick. However, Grainger offers a sweet deal because I am retired from a company with whom they do a lot of business. As a retiree, they sell to me at wholesale price. If there is something on their website that is not in stock, they will drop ship it to my house and not charge me for shipping! This piece of threaded rod cost me $4.44, and was dropped off at my door in about $6.00 worth of packaging. :lol3

    Ray
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  13. WU7X

    WU7X The Old Fart

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    My neighbors house is for sale. Would one of you guys please move in next door?
    Oms, David4 and bpeckm like this.
  14. bpeckm

    bpeckm Grin! Supporter

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    Love it ^ .....!!

    Yah, can you imagine the fun we could have...!! FXRay can be the association president, and we'll all follow along, trustingly......

    Merry Christmas and Happy Happy to everyone out there!

    :photog
  15. fxray

    fxray Long timer

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    WU7X, Thanks for the sentiment, but I can't move to Spokane because (1) It costs too much to live there. (2) Politically I'm way to the right of Ted Cruz. (3) Your riding season is even shorter than in Illinois.

    Other than those probable misconceptions, I've heard it is a beautiful place to live. :1drink

    Some thoughts on piston rings:

    I really only removed my cylinders for cleaning reasons, and to replace the PRT seals. Then I was sort of overcome with Project Creep. I have honed the cylinders and was on the fence about ordering new rings or re-using the old ones.

    Several threads on here talk about people receiving new OEM BMW ring sets with out of spec (too large) ring gaps. I was also unsure about handling multi-piece oil rings. I was going to just clean the existing rings while still on the pistons, measure their side clearance, and, if that was good, stick the pistons back in. Then I noticed that my oil rings were different from one cylinder to the other. That seemed a little strange, so I went ahead and removed them. I have new OEM rings coming from Motobins. Here the expanders from my old oil rings. Maybe it wouldn't make any difference, but???

    [​IMG]

    On the top compression ring, I found no marks or etching. The top of the second compression ring says "ATE" on one side of the gap, and "Top" immediately on the other side of the gap.

    I knew about ATE brakes, but I didn't know they made piston rings too. When I tried to google "ATE rings", I got a lot of hits about dogs eating their owner's expensive wedding ring sets, but not much about BMW. :imaposer

    Anyhow, I've been doing some more reading about ring gap. I don't think I'm too worried any more. Ring gap that is too small is bad because if the ring expands enough to butt the ends together, the ring is likely to break. On the other hand, too large a gap doesn't seem to be as big a deal as it was once thought to be.

    If you are interested, here are some related links:

    This first one has caused a stir on various internet forums. It is from the Institution of Diagnostic Engineers -- Ring Gaps versus Knowledge Gaps

    And this from another forum by a guy who used to run a division of Federal Mogul. He is also talking about the advantage of the second ring having a larger gap than the top -- more about second ring gap

    Finally, the Hastings website has some pretty good how-to videos: Hastings

    When my new rings get here, I'll measure and record the gap. As long as it's over the minimum, I'll use the rings and find out for myself how that works out (presuming I can ever actually get this thing back on the road).

    Ray
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  16. Disston

    Disston ShadeTreeExpert

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    Thanks Ray. That's some good stuff. I love to read things above my level of understanding. It makes me feel smart.

    But this is the first time I have seen an explanation of the reason for the too wide gapped rings working. The bit about the second ring gap is a new one and also interesting.

    Gee, your thread about this old bike has become a favorite. And a new tool added to the mix is fabulous.
  17. bpeckm

    bpeckm Grin! Supporter

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    I knew about ATE brakes, but I didn't know they made piston rings too. When I tried to google "ATE rings", I got a lot of hits about dogs eating their owner's expensive wedding ring sets, but not much about BMW. :imaposer

    Priceless!





    ...and I second disston's thoughts, above. This thread is a font of new information, well presented in no-BS way. Truly appreciated!

    :bow
  18. fxray

    fxray Long timer

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    My new rings arrived today from Motobins. They are Goetze, with box marked for STD R90/6, R90 S. Part number is BMW Motorrad 08-700800-00, and Motobins part number is 50410, which I believe is correct. I was sort of surprised to see the oil ring with the coil spring backer, which I had not noticed in the picture on the Motobins website. Going back now and looking, that is what they show.

    I have never installed this style of oil ring, so I did some looking on-line. I ran across some posts on here that confused me. Big Bamboo, and/or BMWrench, if you see this, maybe you can jump in here. The posts that have me confused are:

    this one where BMWrench was talking about the difference in rings for Nikasil versus Iron cylinders

    this one where Big Bamboo shows a picture of the rings for Nikasil versus Iron cylinders

    It looks like I have a chrome plated top ring (at least on its outer periphery), which BMWrench says is correct for plain iron cylinders. Yet, I have the backer spring for the oil control ring, which Big Bamboo says is used on Nikasil cylinders -- not on plain iron cylinders.

    Here's what I have:

    Top compression:

    [​IMG]

    Middle compression:

    [​IMG]

    Oil ring:

    [​IMG]

    Beyond that, I searched in vain for any instructions on how to install this oil ring having the backer spring (if this is right for my iron cylinders). There is a little diagram on the wrapper it came in that shows me to offset the gap in the backer spring 180° from the gap in the oil ring itself.

    [​IMG]

    That makes sense. What they don't say is which side goes UP? The top two rings are marked for top side, but there is no mark on the oil ring. The package does show an oil ring with a backup spring, where they indicate the top side of the ring, but that picture shows a different cross-sectional area than on the ring I got. I mean the lower RH one in the next picture:

    [​IMG]

    The one in the diagram shows scrapers with definite downward slanted faces, while the one I have looks to be symmetrical -- it could go either side up.

    [​IMG]

    Anybody got some help here?

    Ray
  19. fxray

    fxray Long timer

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    I fooled around with the Goetze rings a bit. My assumption for the oil control ring is that either side up is O.K. There are no discernible bevels on the face. I was told once by someone smarter than myself (and those people are easy to find) that a good way to check for a bevel on a ring face is to stand the ring on edge on a glass tabletop (or surface plate if you have one) and press the ring against the surface with one finger. Also have a machinist's square handy. If there is any bevel on the face of the ring, it will be immediately obvious, along with which direction it slants. With these oil control rings, there are two lands, so the method I just described wouldn't tell you much. That is, the ring would still stand up straight. However, examining the lands with a magnifying glass, I don't see any difference with either side up.

    The oil control ring is easy to install. I took the coil spring out of the ring, expanded it and put it into the ring groove on the piston. Then I expanded the oil ring itself and put it into the groove over the top of the coil spring. I offset the joint in the coil spring by 180° from the ring gap.

    I do believe that rings rotate in use, and that exact initial positioning of ring gaps won't matter much. But . . . I'm too old school to line them up like Mr. Ausherman recommends. So, what to do with them? If it doesn't matter anyway, why not do what Mr. Snowbum says? I love it -- he is not content to position them at, say, 4:00 o'clock and 10:00 o'clock, he gets into the minutes, for example, 4:30 and 10:30 o'clock! :lol3

    I followed his advice (roughly), but I may be off a few minutes:

    LH top compression ring gap at 4:30
    LH middle ring gap at 10:30
    LH oil ring gap at 1:30

    RH top compression ring gap at 7:30
    RH middle ring gap at 1:30
    RH oil ring gap at 10:30

    I'll try to post up some gap and clearance measurements later just for reference in case somebody else is going to be following a similar path.

    {Edit}: Here's what I measured. Strangely, I notice that the measured ring thickness doesn't agree with what Clymer wants, yet the side clearance does. Oh well. I am going to run these rings. If there is a problem, I can revisit this later.

    [​IMG]

    Happy New Year!

    Ray
  20. fxray

    fxray Long timer

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    Well, there's not much progress, but a little more foolin' around. I've had some tools borrowed and needed to use them and return them. One was a valve spring height micrometer, used for measuring installed spring height. I tried to use this when I was working on my TR6, but the tool was too big in diameter to fit into the Triumph head. The tool wasn't too fat for this airhead, but it was too tall to work here.

    [​IMG]

    That top spring retainer should actually be sitting on the top surface of the micrometer. Even with the retainer down in the counterbore, the valve stem doesn't poke up far enough to insert the keepers.

    These micrometers make for an easy measurement if they fit. If you haven't used one, basically the idea is to assemble everything normally, except you substitute the mic in place of the spring. Then you spin the knurled knobs to unscrew / extend the mic to a snug fit, and read the height directly.

    The mic shown here is pretty much the standard one that everybody sells for around US $40. I did see one on-line that should work here, but that would involve me buying it instead of borrowing it, so that isn't likely to happen. :lol3

    Oh well, I did it the old fashioned way, with some inside calipers. You really need about three hands to do it this way, and if one hand has to hold the camera, forget it. So this doesn't exactly show everything being held in place for a good measurement, but it shows the span I was looking for.

    [​IMG]

    Then I went looking for the spec, and couldn't find it in the books. I did find a post on here by bmwrench where he said, " . . . There is (an unpublished) spec for valve spring installed height, though: 36mm is the minimum. Anything more than 38mm makes valve clearance adjustment near impossible."

    That agreed well with what I had here: 34.85mm and 35.15mm. Wait, you say, bmwrench said that 36mm is minimum. Well, mine would be there if I just leave out the 1.23mm thick insulators under the spring seat. I would then have 36.08 and 36.38 -- those insulators really are not supposed to be in there anyway

    [​IMG]

    Pokie told me earlier that these were used on the /2 models, but not on the /5 or /6. I found four of them in my engine, and talked to at least one local guru who still thinks they are a good idea. I may just leave them in there. The only harm they would do is add a little more spring force on the cam lobes and lifters. This engine was running with them in there before, and the lobes and lifters look like brand new.

    So next I went looking for specs on valve spring force. I found that on Duane Ausherman's site, where he lists:
    ____________________________________________________________
    Valve springs:
    Wire thickness 4.25mm (0.1673")
    Spring free length - approx:
    Blue or green code 43.5mm (1.7126")
    Brown code 46.0mm (1.811")
    Spring force at test length:
    At 37.6mm (1.4803") 27.84-30.16 kp (61.30-66.5 lb)
    At 28.5mm (1.1221") 70.00-72.80 kp (154.30-160.5 lb)
    ____________________________________________________________

    I don't know the tolerance on the free length, but my springs were very close to the 1.811" listed above. I measured 1.810" and 1.790"

    To check the force, I had another borrowed tool:

    [​IMG]

    This tester lets you compress the spring to a measured height, and provides a digital readout of spring force. The height part of the tool isn't operable, but I just set a snap gauge for one height, and the inside calipers for the other. Here, I had the spring in place and cranked the head down till I got to the 28.5mm dimension as per Duanes's list.

    [​IMG]

    As you can see, my spring measured within range of Duane's listed spec of 154.30 to 160.5 lb. In fact, I'm at the low end of the spec, so those insulating shims under the bottom spring cups may be a good thing to have. :-)

    Both springs (I was only messing with the LH head today) measured good to the specs at both provided heights. I went ahead and assembled the springs:

    [​IMG]

    From here, the plan was to stand the head up on end and fill the port with acetone to see if it would seal, or if it would leak past the valve seat. I learned to do this test over on the Honda forums. I did it on my CL350 Honda barn twin, and the valves all passed the acetone test. I did no further work on those valves, and that bike has good compression and runs just great.

    So, here we go with the airhead acetone test:

    [​IMG]

    If you look closely here, the port is full of acetone:

    [​IMG]

    After 15 minutes, nary a drop leaked past. No weep, seep, or drip -- I might be home free! :clap

    [​IMG]

    So, let's try the other port, and here, we have . . . :doh . . . a leaker! :devildog

    Maybe you can see the little puddle down on the lower part of the squish band area:

    [​IMG]

    This was not really unexpected. The exhaust seat on both heads has some minor pitting. I was hoping to sneak them past. If they had held back the acetone, I'd have run them. I'd better get them touched up. I know a couple of people who are set up for this -- it's time to go see if I can beg a favor.

    Guess that's it for now!

    Ray