Jockey Journal Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
2,574 Posts
Discussion Starter · #1 ·
Got a call today about oil lines for the Triumph twins. Realized I had answered it lots before and thought I would post a little tech. I looked in the archives and found not reference to this, so I hope this is not redundant. If it is mea culpa, mea culpa, mea maxima culpa. .

You have three major parts of the oiling system: Oil tank, Oil junction box, oil scavange feed to the rockers.

Custom/Stock Oil tank: Should have four spigots.

Spigot #1 a breather, usually called a "froth tower" on a stock bike. Looks like a little hat on the oil tank with a pipe sticking straight out of the side. Custom oil tanks are sometimes a straight pipe on top sometimes a curved pipe on top. I have seen them go from the bottom of a custom tank, through the tank above the oil level. The oil pressure makes pressure in the oil tank and it needs to breathe or you will blow off your cap. Often times this breather will need a length of hose put on it to prevent oil from sloshing or being pushed out.

Spigot #2 Feeder Pipe: on stock tank and many custom tanks, this spigot is threaded into the tank and has a big "basket" style filter on it that fits UP INSIDE THE TANK. Thread is 7/8ths 20 and any basket filter will do that has this thread.

Spigot #3. Return pipe. On stock and custom tanks, this pipe will go from the bottom of the tank, through the tank and above the level of the oil. This way your do not fight the oil in the tank when returning oil.

Spigot #4 "T"-ing off of this RETURN pipe is a smaller pipe that will feed the rocker boxes. It is usually located very close to the oil tank itself. Yes it needs to be smaller. It feeds the rockers by scavanging oil off of the return line's pressure and moving it to the top of the rockers through the rocker shafts.

HINTS: Do not confuse the return line with the breather. If your oil tank has a big threaded hole in it and only three other spigots, then you need the basket filter. You can run an external filter too.

Then there is the oil junction box: Why they call it a box, I do not know. This is the two part oil pipe that attaches to the motor underneath the primary cover and gearbox cover. When you look at these pipes from the side, they often look like they are side by side, but closer inspection (stick your big ole haid up under the motor) reveals that when they join together at the block one is in front of the other toward the front of the bike.

This one in FRONT FEEDS the motor.

The one "behind" RETURNS oil to the oil tank.

From the RETURN LINE you get your rocker feed.

So voila, we have : FRONT FEED FILTER, REAR RETURN ROCKERS.

If you remember this little scheme, you can figure out a way to plumb most any universal oil tank or any stock, approximation of stock or custom oil tank.

Cheers and any questions fire away.
 

·
Registered
Joined
·
2,065 Posts
Re: Triumph Oil Lines. . .

wes - the guy who built my motor keeps giving me shit about my oil tank setup & I'd like to know if i really have something to worry about. I'm a pretty smart fellow & I dont see how my setup could be that far off. here it goes:

I bought a custom tank on ebay that was made for a V-twin. I had to fabricate the plumbing on my own to make it work on my 650 unit Trump. What I have on there now is a 1/4" barb for the outlet, a 1/4" barb for the inlet. The inlet is threaded into a Tee (which is threaded into the tank). Inside the Tee I have a plug with a 1/8"
hole drilled in it for the return to the tank & I also have a 1/8" barb for the rocker feed. Inside the tank, the return has a pretty large (1/2" OD) standpipe which lets the oil return above the oil thats already in the tank. I set it up this way because he originally told me that's what sizes the stock setup was. I later found out that instead of 1/4" & 1/8" holes the stock setup was a little larger 5/16" & 3/16". my question is - will the 1/16" difference be an issue or does it not matter because its so little of a difference & its all relative?

The engine builder was also stressing that the standpipe inside was too fat & it holds too much oil before it actually starts to spill into the tank, saying that the volume of oil in the standpipe (maybe an oz.) would put up too much resistance for the oil returning through the 1/8" restrictor I put in the tee.

hopefully you can help me. he keeps saying that the motor will end up wet sumping if I ride at a higher rpm for a long time. I dont want that.

ALSO - while I have your attention. The tickler on my brand new Amal 930 concentric seems to make the float get stuck down so gas spills all over the place until i smack the carb's bowl. I remember you saying that it was pretty common for the new amals to be whacked out - you know of a quick fix for this?
 

·
Registered
Joined
·
243 Posts
Re: Triumph Oil Lines. . .

Thanks for posting this! Do you know which line is which on the bottom of the bsa twins? feed versus return. Its been so long since I took mine apart, i have no idea. Thanks again for a tech post.
 

·
Registered
Joined
·
7,257 Posts
Re: Triumph Oil Lines. . .

.

One key point that Wes did not address, is that the return line must have some restriction to it (inside the tank) so as to create the slight back-pressure that diverts oil uphill via the smaller diameter rocker feed line.

On stock tanks (and visible inside the top of the '71-on oil-frame thru the filler), the rigid tube is pinched off & soldered, and a hole drilled. 3/32" I think it is.

Note in the Triumph oiling diagram below the half-round cut the droplets are falling from in the return standpipe. That represents this hole.

I mention this because some cheaper aftermarket oil tanks do not have any restriction, just a plain tee. You must be sure this back-pressure/diversion occurs, or the rockers will be oil-starved.

****also, VERY IMPORTANT****

The "feed filter" Wes described & pictured below in the tank, is just a metal screen/strainer.

ANY aftermarket external filter must be fitted in the return line.



Here is another thread with some good discussion of Triumph return oiling - http://www.jockeyjournal.com/forum/showthread.php?t=30128

Do you know which line is which on the bottom of the bsa twins? feed versus return.
Re unit BSA -



**Also note re BSA, in the diagram above, that the BSA has a siamesed return lin from the pump, so there is a direct pressure-fed return oil line to feed the rockers and one to the tank. Thus the BSA oil tank needs neither a diversion/restriction nor a tee fitting.

>>edit<<

Apparently just the last series of unit 650 BSA (I believe late '69-'72) was modified at the factory for this siamesed return line (above), below shows the earlier version with a tee inside the tank and two lines at the pump -



.

Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!
 

·
Registered
Joined
·
1,576 Posts
thanks for bringing this back.
i'm having this issue below, does it matter how long the hose is? I want to make a hose that goes up under the gas tank to breath

The oil pressure makes pressure in the oil tank and it needs to breathe or you will blow off your cap. Often times this breather will need a length of hose put on it to prevent oil from sloshing or being pushed out.
 

·
Registered
Joined
·
7,257 Posts
thanks for bringing this back.
i'm having this issue below, does it matter how long the hose is? I want to make a hose that goes up under the gas tank to breath

The oil pressure makes pressure in the oil tank and it needs to breathe or you will blow off your cap. Often times this breather will need a length of hose put on it to prevent oil from sloshing or being pushed out.
No, length shouldnt have any effect...like the primary, it's just vented to atmosphere so essentially all you're doing is controlling/containing any oil mist or liquid.

Likewise, running the hose "uphill", all the better (long as it cant rain into it).

Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!
 

·
Registered
Joined
·
7,257 Posts
How much kicking should it take to get some oil returning to the oil tank on a 650 Triumph?
Takes a pretty good bit, especially on a rebuild and/or w/dry new lines.

Can help to prime/fill the feed line so its full to the pump, but most especially kick with the plugs out where you can really get it spinning.

Even better, plugs out, pushing in the driveway or road in 2nd or 3rd gear.

All else fails check where the lines attach at the tank & at the case/pump -

Forward is Feed, Rear is Return.



.

Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!
 
1 - 17 of 17 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top