Second gear repair, redux

There has been lots of good info posted here on MKI second gear repair. I recently tackled 2nd gear repair on my ’84. While this problem surfaces on all 83s, 84s and some early 85s, there can’t be a lot of those bikes left that haven’t by now run into the problem. Nonetheless, I’ll add my experiences here and “pay it forward”.

Removing and eventually reinstalling the engine is possibly the most challenging aspect of the whole process. The thing weighs in at about 200 kg, and it’s a really tight fit. To help in the extraction (and re-install) I built a small cradle that I bolted onto my floor jack. It cradles the engine oil pan and helps support the engine and adds some stability. The base of this cradle is 3/4” plywood, but if I had to do it again, I’d use 1” hardwood. Other dimensions are - base 11” x 9.5”, 2 x 3s are 9” and 6.5”, set 4.5” part. I added a strip of 1/4” ply on the longer one. The inset hole for a large washer is 1.25”. The hole for the bolt will be whatever size suits the bolt that works with your floor jack.

The engine is extracted from the right side of the frame. All the plastic, including the inner most panel that holds the coolant jug, should be removed to give max clearance for engine removal. (I didn’t remove the inner panel, and regretted it!) After that it’s a matter of raising the engine just enough to clear the rear engine mount brackets. Pull it a bit forward, inching the front out at an angle and it will clear, eventually. After that, have a lift table handy where you can, with a helper, flip the engine off the jack and onto its top on the table. The table lift also proves very useful in subsequent engine work.

To keep track of the 36 case bolts as I extracted them in order, I built a simple stand as pictured, with 40 odd holes drilled. And, having an extra set of hands for flipping the engine top to bottom and back, pays dividends.

In preparing for the 2nd gear repair I purchased an ’84 transmission on eBay that had been repaired. Unfortunately, it looked like it had been sitting around in the engine, or on a shelf, for quite some time and looked rusty. I was reluctant to use it, so purchased an ’87 transmission on eBay assuming it would have the upgraded 2nd gear and thrust washers. This transmission was in pristine condition BUT did not have an upgraded 2nd gear. Not sure what happened with that! So I decided to do some mix and match of the three transmissions I had in hand. After reading some threads on this forum I realized I needed to be careful with the middle gear. If I didn’t retain those parts from my original transmission I’d get into gear lash problems. ( There are shims, installed at the factory, at the left end of the drive axle, that ensure correct alignment of middle gear components.) So, I removed the middle gear components from my original 84, aiming to install them on the 87 drive axle. The stand I constructed, based on info I found on the forum, made it easy, using a small hydraulic jack, to compress the middle gear spring and extract thrust washers from my transmissions. The stand is made of 2 x 6s with the three cross members held with lots of #10 screws. The top member has a 2” hole and sits about 11” above the middle one. The middle member has a 1.25” hole to guide the jack and axle shafts. Once the middle gear spring is compressed, the washers can be picked up most easily with a wand magnet. After that, middle gear parts are easily removed.

Using this stand I was able to disassemble three transmissions, aiming to build one good one. I used the ’87 transmission and components, but installed the much wider upgraded 2nd gear wheel from the eBay ’84, plus all the middle gear parts from my original ’84. As a bonus the eBay 84 transmission also had the upgraded 5th gear pinion, which seems to be unavailable for purchase. I used that. I replaced all clips with new ones, and of course installed new thrust washers.

With that it was ready to reassemble. Before doing so, I made sure those little tabs on the transmission bearings were pointed in the correct direction, and slightly raised so they would fit into the corresponding pockets on the lower case. Also, I made sure that the shims at the end of the drive axle were pushed hard right, away for the inside side of the case. I used a screwdriver to lever the drive axle to the right to help in that regard. Having the shims hard right helps prevent shim damage when dropping the lower case into place. Later, when the cases were together, I knocked the axle to the left and forced the shims hard against the cases. I used Hylomar Blue as a joint sealer. With the shift arms on the lower case in neutral, I dropped the lower case onto the top, using a long screwdriver to make sure the arms dropped into the proper transmission grooves. I then shifted the transmission through its gears to make sure all was working properly. An old Yamaha shift lever helped.

For a really good illustration of how to reassemble the cases, purchase the VMax video by Damon_Ferraiuolo@msn.com.

At this point it’s a really good time to think about replacing the rear exhaust joint, assuming you can find something better than what you have. You’ll never have a better opportunity!

Along the way, I upgraded the shift cam as per pegscraper (http://www.venturerider.org/forum/showthread.php?40713-Clunky-Shifting), installed new Barnett clutch plates and springs, added a new clutch slave cylinder, and installed stainless steal brake lines.

If you feel compelled to check gear lash, now would be the time to do it. The Damon VMax video will show you how. You’ll need a dial indicator, with magnetic base, and something to hold the middle gear nut firmly. I used a piece of angle iron, in which i drilled two holes strategically located to allow me to bolt it in place, using middle gear bolts, with its top firmly up against one side of the middle gear nut. To locate the precise location of the holes I used a thin piece of cardboard whose straight edge I held up against the nut, and with a small amount of oil on the middle bolt holes, I was able to collect the proper hole locations. Once transferred to the angle iron, a drill press did the rest. Now the with the angle iron bolted in place and the middle gear held firmly, you can position your dial indicator on it, turn on the magnet, and get a measure of gear lash. Mine was within spec.

Getting the engine back in the frame is very challenging, and definitely a two-person, if not three, job. First it’s going to be a two-person dead weight lift to get the engine off the table and into the cradle on the floor jacket. The engine is somewhat lighter then when extracted since most of the heavy side parts, stator, clutch, etc, are removed, but still a heavy beast. Second, there is not a lot of frame clearance for inserting the engine. The thing has to be raised and angled in just so. We kept frigging with it and eventually got the arse end in and settled up and over the rear mount brackets, making sure the differential slopped into the receiving cavity. After that we were home free.

Once the engine is bolted in place, it’s time to turn to slipping the differential rubber boot over the rear of the engine. There are tabs on the boot that help, but you’ll need a long screwdriver and needle nose pliers to get it on. More challenging is reattaching the spring wire. I attached a small piece of wire to one end of the spring wire. With a slight curve in the wire, I pushed it under the boot and grabbed the other end when it appeared on the other side of the boot. Working with two needle nose pliers I was able to pull the spring wire into the boot groove and get the two end hooks, hooked.

I then took the rear wheel off. This had also been removed prior to engine removal, allowing me to extract the drive shaft, and then reinstalled. Now I had to re-install the shaft. With all splines moly greased, I slid the shaft into the cavity, and by rotating clockwise and pushing, it picked up the dangling engine differential and slipped right into place. I read about the twisting trick somewhere, perhaps on this forum. Whatever, it works like a charm.

After that it’s just a matter of getting all the engine parts bolted on, wires reconnected, starter and rad installed, carbs settled in (getting those babies in place deserves a whole separate write up!), and so forth. Installing the mufflers is a nasty piece of business, especially the middle exhaust collector. With the motorcycle up on a lift and on my back looking up, I can ram and wiggle the collector into place and over the rear exhaust joint pipes and onto bolts that will hold the collector in place. Adding nuts to these bolts is relatively easy with an extension bar on your ratchet. Reaching the bolts on the securing bands of the rear exhaust joint pipes is not so easy. With a wobble extension bar, and with the centre stand pulled down out of the way, I can, lying on my back, just reach the band nuts and tighten. NOTE, don’t snug the collector completely into place until you have the front exhausts in place. The rear exhaust pipes are easy to install. I can’t imagine installing an exhaust system without a lift! (BTW, some time ago I added ’85 exhaust pipes and foot rests. The latter look much better than the stock 83-84 ones.)

Last, I replaced the ’84 starter with a 4-brush one from an 06 I picked up on eBay.

Before test driving, I synced the carbs with Carb Tune. They needed it!

It was a tense test drive, but things worked perfectly. Very noticeable smoothness in transmission shifting, and of course 2nd gear works wonderfully. And, guess what, dropping it into first gear at start up produces a simple click, and not the loud clunk and lurch I had become accustomed to. The new clutch parts, or new transmission? A four-brush starter is a very worthy upgrade.

We’re good for another 30 years!

Well done, Glen!

Barkeep... Can we make this a sticky?