Fusing oil lines to convert TX engine to wet sump

[scrambler]

Hi All,

I dismantled three engines recently, including an upgraded one with deep sump and another one (my bike) with a huge automotive oil filter and cooler. All of them had serious issues due to low efficiency of lubrication. For instance, none of the transmissions was ok, 1st gear teeth were badly worn and cracked. This is not acceptable and gives me the impression that these engines are really badly engineered and the upgrades on 74 bikes didn`t solve all the issues at all. I looked at many transmissions on ebay and most of them, as far as I could see, are worn and have pitted gears. I read somewhere here that these bikes could make even 100k miles without serious problems. How is that possible?

I`m a little concerned now that I spend a shitload of money and time on this engine and eventually it`ll die of oil starvation. I was wondering, perhaps the two oil lines should be fused, then the two pumps working together would lubricate everything in the engine excessively. The deep sump would work then as a real oil pan like in a wet sump engine and the oil tank would no longer be needed. Thoughts?

[supercub]

I would say that leaving as stock would be the least risky. From the various barn bikes that I have brought back to life, I found people just beat the hell out them, maybee because they were so inexpensive back then. Also poor maintenance, bad wrenching and poor quality oils degraded them. An added oil pressure gauge would let you know if it is getting proper lubrication.

[scrambler]

[scrambler]

[scrambler]

Hey, I uploaded some pictures so you can see what I`m talking about. I have four transmissions, I just bought one on ebay. The 1st gear is damaged on each. This is not maintenance or oil issue, it`s bad engineering. Has anyone here seen a gear that didn`t look like this? 4 out of 4 is a high sampling... And it`s one piece with the input shaft.

[supercub]

Looks like a rough grinding or machining finish to begin with, then the mating gear galled the rough surface.

[supercub]

Most of the stuff on ebsy has been cherry picked through. Alot of people just relist stuff that they brought and found to be worn. Best is a complete engine that a dismsntler or part out person listed and the fastners show no sighns of wrenching, old oily accumulations still intact.

[scrambler]

My impression is that most stuff on ebay is from dismantlers who are selling lots of parts from different bikes. I bought only one trans on ebay though, I messaged the seller that it`s damaged, I try to send it back. The other three are from my bike and two donor engines. All four show they same damage, kind of abrasive wear. Only on 1st gear, I guess because the torque is the highest in 1st. I`m thinking on buying a new input shaft now and then increase the amount of oil flow somehow these gears receive.

[albaljeu]

GO here and contact Nick Clarke, he built a racer and converted it to a wet sump engine. He also published a book describing the build...not sure if he has any left though.

www.tobyfolwick.com/tx750/ownerpg.php

[scrambler]

Ah, cool, so I`m not alone with this idea.

[supercub]

Toby Folwick has alot of articles on the TX. One of them describes opening up oil passages in the cases, if your all torn down, worth a try. From your pictures it looks like the gears were broach cut by the straight tool marks across them. Finishing them off with fine emery cloth wrapped over a sheet metal strip would help. There is a mod that I read somewhere for dermeling the shift drum slot for easier to find neutral.

[bigskyforever]

I have torn down three of these engines one having 40,000 miles and the transmissions are in good condition. From the wear on the gears, your engines must of an a long time between oil changes. Although lubrication is not abundant on this engine design there is no discoloring of the metal to confirm your theory.This would indicate oil contamination. Oil change on these bikes are 2000 mile intervals. Also the issue of poor clutch comes to mind.

[scrambler]

Bigsky, I just bought a brand new input shaft, and the machined surface of the teeth is quite rough on it. Probably the combination of this, the high torque and the oil together is responsible for this pattern. I will increase the diameter of the bronze orifice that supplies the transmission just in case.