Topic: custom oil tank

[Ernest]

I going to be customizing my cb750 to cafe style racer and right now I'm just brainstorming some ideas that I have for the bike drawing inspiration from others like Benjie's cafe racer the Goblin.  Notice how he has the section open where the battery was.  Well, I want to do this also only instead of leaving that space open I want to put  a drum style oil tank with a battery compartment notched out of the tank in that space.  Like this one that you usually see on choppers.

My concern is what all I will have to change to the stock oil lines to use this type of tank.  Look at the bottom  of this kind of tank that shows three 1/8" NPT and one 1/4" NPT. The three are feed, return, and vent.  The one 1/4" is the drain.  Will the stock cb 750 lines work with this kind of tank and whats the vent for?
Also what is this thing inside of the stock oil tank? 

[Lumbee]

...sup Ernest...you def don't wan't to starve the engine of oil...I wouldn't go any smaller than 3/8 fittings.  Hers a pic of my oil tank on my chop...

http://pg.photos.yahoo.com/ph/marklocklear/detail?.dir=8c67&.dnm=ec13.jpg&.src=ph

the tank has 5/8's fittings (bungs) welded into it, and I used 3/8's fittings with the ribbed end to slide the lines one.   Check out cycleOne http://www.cycleonemanufacturing.com/custommotorcycleframeaddons.html  They do an oil tank with the batt box on the back side...not the cheapest, but their quality is A #1. 

As far as the stock tank...this might help...I think the square thing my just be to catch some of the overflow oil.  Vent and overflow are the same tube...it just allows any air pressue that might build up to be released, and if u put to much oil in the bike it allows the oil to escape the tank and drain to the back of the motor.

http://pg.photos.yahoo.com/ph/marklocklear/detail?.dir=d023&.dnm=bdb1.jpg&.src=ph

[Ernest]

thanks for the pics.  I wonder why they would put 1/8" on their tanks.  Is that what harley's are using?  I imagine I will have to make my own tank on the cheap and it's a good thing I asked about the lines.  I'm asking questions without even really getting into the bike.  I've got a couple more weeks of a home improvement project I have to finish before the wife will let me start on the bike.   So what size fittings should I weld to a custom oil tank that will allow me to use the stock oil lines or say Carpy's braided steel lines?  3/8" NPT or 5/8"?

the tank has 5/8's fittings (bungs) welded into it, and I used 3/8's fittings with the ribbed end to slide the lines one.

I guess I don't understand what your saying here but I am alittle punchy.

[Lumbee]

...sorry Ernest...that doesn't make much sence does it?     I think the fittings that were welded into my oil tank are 3/8's.  Then I screwed fittings into the tank so I could attach the oil lines.  I guess what I'm saying is the fitting that allows you to attach the lines will actaully be smaller (and restrict the oil flow) than the fittings welded into the oil tank.

You  should email  Carpy...I'm sure he can give you the facts.  As far as using the stock oil lines.  You will use the fitting that connects to the engine, but I don't think u'll be able to use the one that connects to the stock oil tank.  I'm not sure what size that is, but just about any aftermarket tank u get will be american, and hince standard to metric sizes.

[dusterdude]

i know im going to start a war with this,yes h-d tanks use 1/8 pipe fittings with 3/8 hoses attachted to them and they work just fine and i dont want to hear anything about how our bikes turn higher rpm`s and all that stuff.as long as you have good flow to the pump 3/8 lines will work.ok,ya`ll hammer down now.

[ProTeal55]

I agree with DusterDude on this one...
HD's have 1/8 npt fitting that go to 3/8 line.
Even the $40,00 and up dollar custom bike syou see on TV have the same setup.
All on the quality of the pump to move the oil around...

[Lumbee]

...so how big are the stock oil line fittings?

[dusterdude]

im not sure what size the inside is on the honda hoses,i will say the od looks rather large.i have noticed that before.

[Lumbee]

...I'v heard 1/2 inch...not sure what the mm equivalent is though...

[Lumbee]

...OK, here ya go...

"Honda sohc Oil line fittings:
                                              Here's the deal: Honda 750 sohc oil lines are 1/2 inch inside diameter. So after you grind or cut-off
                                              the crimped on clamp that attaches the oil line to the motor you can install new oil line. But most of
                                              the oil tanks we are using come from the Harley world and use  3/8's inside diameter oil line.
                                             Here is what we use: These fittings will fit all HD custom oil tanks and will accommodate 1/2 inch
                                             inside diameter Honda oil lines. Problem solved. ( cool hey)
                                              Now that we solved your problem, Run out to your mail order sleaze bag and buy them cheaper.
                                             $ 11.95                     # OL-722"

..this is from kens web site...  http://cyclexchange.net/Oil%20System%20Comp%20Page.htm

[dusterdude]

ok,i knew the honda line looked bigger.

[cd811]

I made up my tank. my fits are 1/2. the honda id IS 1/2. so I didn't want to mess with a good thing so went with 1/2 feed and return. the vent is on top where it needs to be. the return is lower than the feed to allow oil to cool and cut back on possible contaminates. I used a 5inch steel pipe and the ends are 1/4 steel. pics are in the gallery under cd811. I did it just to say I did it. ya want save money over a store bought.

[Ernest]

I made up my tank. my fits are 1/2. the honda id IS 1/2. so I didn't want to mess with a good thing so went with 1/2 feed and return. the vent is on top where it needs to be. the return is lower than the feed to allow oil to cool and cut back on possible contaminates. I used a 5inch steel pipe and the ends are 1/4 steel. pics are in the gallery under cd811. I did it just to say I did it. ya want save money over a store bought.

Nice work, That's 5" diameter pipe and what length?



I can't tell If you modified the frame or if that space you have the tank in will be the same for my stock 1974 frame.  It looks like it will work though.

Where could a person off the street go to pick up 5" diameter steel pipe sections? How did you get the ends cut?

[dusterdude]

if i was going to build a tank i would use aluminum.if you use aluminum you can go and buy two aluminum pots and weld them together.

[ProTeal55]

CD811----> Awesome setup, very clean.....

A good source for raw alum. and metal is a local chassis shop. Any place that builds racecars , rollcages , etc is a
good place to get supplies for projects like this. Sometimes you can even raid their scraps/garbage and find
what you need.

[cd811]

thanks for the flowers!
the town down the road has a metal shop that makes a lot of agricultaral stuff, so I just walked around and found some scrapes for $10. fits are from lowes. a buddy of mine did the cutting and wieldin for $60. yea aluminum would have been cool, just did not work that way. my frame(around the oil tank) is altered some. the top(driver seat area) frame was lowered, so actually if your frame is stock, you should have even more room. the motor and tank together will hold a gallon of rotela 10-40 easy. I'm at work, so I can't measure the length of the tank, so I'll get back on that(it just barely sticks out on either side)

[Geeto67]

is there any problem with using a hard line with a 1/2" inside diameter?

I am building a combination tail section and oil tank and I want to use 1/2" ID hard line to route it along the frame rails. any rpblem with this?

[dusterdude]

geeto,i wouldnt think so,harley`s used em for years.

[Geeto67]

I didn't think so, plus copper lines look so cool, like a still on wheels.

[dusterdude]

be careful with copper,i believe its a tad more brittle than steel line and will crack easier.

[cd811]

I measured the length...11 inchs
after looking at my frame, the triagle does have several alterations but it will still fit on stock,(the front part of the triangle was altered also)
no, I don't see a problem with solid oil line just sitting it up.
rubber is easier.

[ProTeal55]

Hard lines always look nice when done well.........
Watch out for Copper , it doesnt take much to crack when bending...

[paulages]

if you are making a custom oil tank, how do you determine capacity? obviously, a bit of 6th grade geometry can determine the capacity of your new oil tank, but i'm wondering if there's a balance of oil in the tank and engine required to keep the oil cool enough as it's cycled.

[cd811]

for some reason,i understood your question...lol...ok this is my thinking...the engine itself doesn't "hold" that much oil...in my equation I would try to get as close (if not more) to stock quanity

[paulages]

yeah, that's what i figure. unless someone can knowledgeably explain to me how a lesser quantity of oil will suffice, i'll stick to what i know works. what i wonder though, is how much oil is in the engine while running, and how the quantity over that was determined.

[bill440cars]

       Hey CD, good to see that you're still alive and kicking. Nice to see your bike's still in your avatar also.

                                                            Later on, Bill