Digging into the Guzzi part III

Thanks to some found money, I opted out of fabricating my own special tools for the V700 and instead purchased some from MG Cycle. The flywheel/ring gear holder will obviously lock everything up to allow removal of the generator drive pulley, timing gears, and then ring gear, clutch, and flywheel removal. The other tool pulls the rear bearing carrier.

In action, using the 3-tooth part to hold the ring gear for the starter. The single tooth on the top is used later on, after the ring gear is removed, to hold the flywheel in place.

This pisses me off to no end. As mentioned previously, this bike had a lot of work done to it in the 70's. Apparently besides new cylinders, pistons, and a top end job, they also put in brand new clutch plates. What I don't get is, why the hell you wouldn't replace the transmission input seal while everything was apart. Because they didn't take that step, these brand new clutch parts are completely ruined by gear oil. Such an expensive waste...

Timing gears. You can just make out the scant timing markings between the cam gear (big) and the crank gear (small). These were wiping off when I put my finder on the gears, so I had to make my own new markings that were more obvious.

Took some white out for the time being, need to clean it up a little on the cam side, but it'd be hard to mess up alignment for timing now.

And this is where my work ended for today. Shockingly, I don't have a 26mm socket or box end wrench anywhere (in fact what I have goes up to 24mm, then skips to 27mm and up, so timing gear removal, and subsequent bottom end disassembly, will have to wait for another day.

major parts deliveries

I'm still waiting on a major order to come in from Max BMW, namely bottom end spacers, bearings, etc., and I still need to get the crankshaft rebuilt, but I'm beginning to see signs of a complete engine after the parts delivery today.

+2 Timing gears, 30 degree - new style

Remember that $50 box of parts I got way back when? Well, a couple things I was able to salvage for this build was a new type oil pump gear wheel and crankshaft lower timing gear. The lower gear was kinda strange because it's a 0 and the correlating timing gear in the box was a -3 (these early BMW engines don't use timing chains, they use precision gears sized to the crankcase and ranging from -10 to +10). My case is a +2 so that was a no go, but I kept the lower gear as cases shrink over time and figured I may need it when I buy +2 gears and find that they fit too tightly. Now I have +2 gears, so we'll see what happens.

These gears are the new style, meaning 30-degree (so they work with the new-style oil pump wheel I kept), and they'll accept the new style breather plate (much improved from the pin-style) which also came with the box that keeps on giving. I got these from S.Meyer in Hillesheim, Germany and they were about 30% cheaper than what BMW was asking. I was a little concerned about the price being so cheap, but they look and feel OEM and seem to be very high quality. Now I can completely cross the cam-shaft parts off my list, and with everything else for the crank on order, that'll be complete as well. Once I get the parts in and the crankshaft rebuilt I'll finally have a complete bottom end.

Concerning the top-end, I'll admit that I was kinda stressing over things. I was able to get the cylinders no problem, even got em for a great price, but good heads are somewhat difficult to find. One of the big reasons is the most commonly found heads are ones from the early to mid-1960's. The issue is heads in the 60's were prone to bad metallurgy (due to environmental concerns, the alloy used in the casting was changed) causing, exhaust threads to melt away like butter and rocker posts to literally sink into the head. Duane Ausherman actually coined the term "butterheads" to describe them.

BMW Bulletin #244 dated 7 Apr 67 claims:
The material of the heads was previously changed to avoid the use of chloric gas required to clean the equipment that handled the former "hydronalium" alloy. 
Going on to say: "it has been found that the new alloy does fully equal the hitherto used alloy concerning its resistance to heat"

They also developed cracks in the combustion chamber and tended to launch their spark plug inserts. BMW's solution was Lange Kerz (long spark plug) or "LK" heads that used an entirely new alloy. My choice was essentially either find really early heads with the quality, pre-pollution laws, that don't crack or melt, or find LK heads. I wound up getting a great deal doing the former.

1952 R51/3 Heads + Rockers

I'm pretty stoked about these heads. You may be wondering why I'd get R51/3 heads for an early R60, but the R51/3, R67, R50, R60, R50/2, and R60/2 all shared the same heads and valve sizes (with varying metallurgy as mentioned previously). Note the 2 different valve springs (per valve) and the thick cooling fins that identify this as an early head. I know a rebuild of these will occur somewhere down the line, maybe even convert to rotating valves, but once my bottom end is together I'm going to bolt these right up and test the compression. If found to be within spec, they are staying on, at least until the next winter...