Boxerworks.com

Rather than reviving a 6 month old thread (that degraded partially due to inside paint on peanut valve covers) I'd like to start a new one ... with a twist:

I have come as far as realizing that it is a bit a trial and error thing to install a crankshaft, but it is not rocket science. I think I can do it. Book says to start with two 'red' thrust washers which are the thinnest ones. Torque everything up incl flywheel and measure axial play with a dial gauge. Depending on result use a thicker thrust washer in the rear location. Tolerances are in 'the books'.

Now, in my case, none of the parts I am intending to use originally came from the same engine. All by themselves they will be in spec. So in order not to need to buy the whole range of thrustwashers (assuming 25% or more re-stocking fee), I see my options as follows:

1) Find somebody that has a lot of those thrust washer in a box (old/nicked/dented/only good for trials) that you can borrow to figure out what you need to buy (cons: twice shipping, Pro: solution allows to test extensively without fear of damage)
2) Have thrustwashers simply replicated in hardened steel from a machinist, pretend they were the real deal, use them during assembly to figure out what you need to buy (cons: do cost of fakes outweigh shipping cost?, need drawing)
3) Buy the two 'red' ones, do the experiment and then buy what is needed (cons: two orders, two shipping cost etc)

I am not starting yet, just making sure there are no long term obstacles once I start ... which won't be before Fall of this year. I would like to visit either Ken or the FoF in 2012, so there's my timeline.

Stephen

Those shims are made of very soft material, similar to the main bearings. At least that is my memory.

If you use used thrust bearings, make sure they are flat flat. Sometimes they are a close fit on the locating pins. If care isn't taken removing them, that is: working them off each pin a little at a time, they will bend very slightly. This can make make the measurement misleading. I found this out the hard way. I had a bunch of used shims to pick from when I did a set up and thought I had good clearance, but the idle would slow down a couple of hundred RPMs when the clutch was pulled. I replaced the rear shim and all was good.

There may be a way to make a ring from hollow core solder that will compress to the space available? I have used solder for measureing squish and the results are very repeatable.

R90Steve wrote:If you use used thrust bearings, make sure they are flat flat. Sometimes they are a close fit on the locating pins. If care isn't taken removing them, that is: working them off each pin a little at a time, they will bend very slightly. This can make make the measurement misleading. I found this out the hard way. I had a bunch of used shims to pick from when I did a set up and thought I had good clearance, but the idle would slow down a couple of hundred RPMs when the clutch was pulled. I replaced the rear shim and all was good.

There may be a way to make a ring from hollow core solder that will compress to the space available? I have used solder for measureing squish and the results are very repeatable.

Oooo, that seems like a very good idea . . . BUT, you mean "solid-core," don't you? you wouldn't want flux getting squeezed out in there.

Major Softie wrote:

Oooo, that seems like a very good idea . . . BUT, you mean "solid-core," don't you? you wouldn't want flux getting squeezed out in there.

Does sound a bit messsie, doesn't it? I have tried solid core for mesureing squish and it just doesn't work very well. Actually I have had no mess using rosin core. The size of the solder does need to be fairly close to the size of the gap, so you aren't squeezing the holy bejeezus (rosin) out of it.

FWIW Stephen...
I have used this stuff to measure bearing clearance -
http://www.plastigauge.co.uk/
Doing my final drive I cut spacers out of an aluminium beer can ( 0.1mm, 0.004").

Thanks for your input, guys. I looked closely at the cost associated to actually do the job (mainly jigs/fixtures and tools, mainly in-/outside micrometers) and correlated that with the possible risk of screwing it up or not getting it right whichever comes first (or whatever other excuse I may find not to do it).

In the meantime I conversed with Nathan about the possibility of just have camshaft and crankshaft installation and some associted work done to the block.

The above coupled with the US economy seemingly having a need for some monetary injection and my expressed support for places like Boxerworks Service with Nathan, Tony and the others, I will have Nathan and his team take care of my block. That 600 engine is a midterm project and I should have it installed and running by next season (2012).

Speaking of projetcs: I have a 750cc engine available as a spare and was thinking about building another (definitely last) Franken, maybe a 70's ISDT bike this time?

Whatever it turns out to be in the end, If you had a rolling chassis (/5 preferred) in your shed, neglected but sound, not going anywhere ever, straight frame, with clean papers, talk to me. Now or later ...

See you guys on the road.

Stephen

Is that the Nathan who was so very bad to our Matt?

Chuey