ATTN: ALL BTR Builders (Gravely Model L)

[wayne z]

This was actually one of the topics of conversation all that needs done, lol, cap em by heli arc a plug in place tap a oil port in the crankcase re-route the oil lines using an oil tank with vented cap. problem solved he is sending me a diagram to make sure all is done proper I will post it when I receive it. He said there was going to be some mods required to use these engines for this application , But well worth it in the end. They are capable (when built right) of more then 12 hp goverened. Lots of old school hop ups and mods if you want to take the time or spend the money.

That would be great to see the diagram. I want to understand how the pumped oil gets back to the tank and where the crankcase vent needs to be.

These are some realy awesome bulletproof engines. You could prolly run them up to 3800-4000 or so intermittently with no probs. I know that the several ungoverned ones that I have owned have been revved pretty high.

 

[wayne z]

OK, I've been studying my engine and trying to figure out the best and easiest way to apply it to a motorcycle. This is what I came up with. Any inprovements or other suggestions are welcome.

I think that the fan drive side of the engine should be used for pto on a motorcycle build. This end of the crankshaft runs in tapered roller bearings and can withstand extreme side loads from a belt or chain drive primary.
The other end of the crankshaft, the original PTO end, runs in a bronze bushing, and originaly drives a planetary gear, with hardly any side load at all. This end would not be good to adapt to a side load, also there is no way to put an oil seal on the bronze bushing.
The other issues are where to and how to have an oil resivoir, and crankcase breathing.

I am going to try using the fan pully for primary drive, to a 3 speed tranny. Then building a round pan that completly covers the original PTO side, with a rectangular portion extended below the crankcase to act as an oil resivoir. The engine can burp the pumped oil into the pan with baffles maybe and a breather on top, and the oil ends up in the sump, which feeds the single oil pump of this engine.

A magneto mount could be built into the top of the pan, for direct coupling. But I like the idea of a remote mount with chain drive from the fan side.

 

[RicksRides]

I am looking into replacing the bronze bushing with something more substantual a bearring and seal perhaps nothing is undoable with proper toolage, the great thing about all metals is you can add to it, remove it and shape it in any form you want. I also will use the fanside to drive the machine. plan on belt to belt then belt to chain custom pulley off the second engine. There is likely more then one way to skin this cat (so to speak) Im sure with the resouces available to us we will find a suitable solution. There are a number of issues to using these as bike motors,my research has not found any bikes/motorcycles with this powerplant. These will truly be unique builds, wether single or dual engines. I was digging thru some old parts and found a 4speed from a mid 70s Norton Camando 850???? aslo have a 3speed pre unit of an ole beezer (BSA). hoping one of these should prove usable. Also downloaded the frame drawings and specs for a 1913 model 9e HD itll need stretched 5 inches to allow for dual gravelys theyre bigger then the little 32 C.I. twin of that year. I/We find a way to use these and im thinking bout keeping the engines I have for personal builds I really love the look of them. Ok Im rambling to much corn squeezing's off to bed I go

 

[wayne z]

OK, It finaly came to me while studying an IPB of this engine. This needs to be researched.

It may be possible to build one of these engines with two right side crankcase halves, and two right side crankshaft stubs mated to the flywheels. Might take some careful machining or align boring or pin placement, but prolly quite easily done.

Then the problem of good bearings and seals and easily adaptable PTO would be solved.
A crankcase breather could be easily added up high on one of the case halves.
A second oil pump would be needed to scavenge the crankcase and send the oil back to the tank, or a sump lower than the crankcase could be used instead.
I'm gonna go visit my neighbor and his pile of Gravely parts tomorrow and see what's what.

 

[RicksRides]

Cant wait to hear back from ya never thought bout trying that

 

[RicksRides]

Picked up my tubing today 1 3/8 13g 1 in 13g and 3/4 13g Think itll be strong enough

 

[RicksRides]

Also found this rough ole thing today what was it? lol

 

[curtisfox]

Not sure, but the bike looks like it could be a 1935 Schwinn B10E Motorbike. Never had a motor, just Motorbike Style. Do you know if it has a badge and whats on the badge?? Even if its not a Schwinn, its circa 1935. Missing all the good stuff like tank and truss rods etc......Curt

 

[Mr.B.]

That does kind of looks like a Schwinn “Sweetheart” chainring...

-Kirk

 

[RicksRides]

Its in Ruff shape but if someone wants it ill ask him what hed take for it. should be too much

 

[RicksRides]

Im going to beef up both these engines, as they sit they are 6.6hp and 190inch pounds of torque Im looking for close to 10 hp out of each and torque in the 215 inch pound area, giving me around 20 hp and 36 ft. pounds of torque. Pics below show mock up of how they will sit

 

[wayne z]

Im going to beef up both these engines, as they sit they are 6.6hp and 190inch pounds of torque Im looking for close to 10 hp out of each and torque in the 215 inch pound area, giving me around 20 hp and 36 ft. pounds of torque. Pics below show mock up of how they will sit

I can tell that this is gonna be awesome! Can't wait to hear what it sounds like.

 

[RicksRides]

It may be possible to build one of these engines with two right side crankcase halves, and two right side crankshaft stubs mated to the flywheels. Might take some careful machining or align boring or pin placement, but prolly quite easily done.

Wayne, A couple of us were going over your idea. so we bolted 2 rear cases together. Heres our findings and conclusions. These cases are matched sets, we mixed matched 3 rears they all end slightly off (cocked)
at the crank berrings case halves #1&#2 off by .054 case halves #2&#3 off by .046 case halves 1 & 3 off by.049 Those measurements are beyond the allotted tolerances.
This was done by 3 small dial indicaters installed by pinning them in there, turning the pins tightened them in place.
He turned down some round stock to proper diameter slid it in space and took measurements. If I'd known this was going to take place i'd a brought a camera (I dont have one on my phone). This was a cool thing to watch, as I simply brought up the subject. From this we come to the conclusion that its off enought to eat up bearrings and maybe more. You can only assume the cam journals are a similar story. this problem could possibly be overcomed by line boaring the cases in those 3 spots and installing the new oversized bearrings and bushings but I dont even know what sizes to use or if their even avaliable.It could be creating new issues.

 

[RicksRides]

I was going to do my own machine work, but after seeing these 2 older guys working I think Ill pay them. They really know their stuff. Maybe I can trade em some Gravely stuff.

 

[RicksRides]

Does this triple tree look sturdy enough for my 1913 HD twin tribute. the holes for the forks are for 1 in tubes its cast not billet, casting is 1/4 in thick and little thicker as it moves into corners.the original neck tube is 1 3/8 ID shown in yellow. I have others if these wont work.

 

[wayne z]

Wayne, A couple of us were going over your idea. so we bolted 2 rear cases together. Heres our findings and conclusions. These cases are matched sets, we mixed matched 3 rears they all end slightly off (cocked)
at the crank berrings case halves #1 off by .054 case halves #2 off by .046 case halves 1 & 3 off by.049 Those measurements are beyond the allotted tolerances.
This was done by 3 small dial indicaters installed by pinning them in there, turning the pins tightened them in place.
He turned down some round stock to proper diameter slid it in space and took measurements. If I'd known this was going to take place i'd a brought a camera (I dont have one on my phone). This was a cool thing to watch, as I simply brought up the subject. From this we come to the conclusion that its off enought to eat up bearrings and maybe more. You can only assume the cam journals are a similar story. this problem could possibly be overcomed by line boaring the cases in those 3 spots and installing the new oversized bearrings and bushings but I dont even know what sizes to use or if their even avaliable.It could be creating new isues.

Thanks, I was on the verge of buying a whole 'nother tractor to find out..

So, can you ask your guru's if it would be possible to align the bearing bores and then re-bore the alignment pins? Or add them elsewhere ? Two outboard cases would also take care of the 2nd oil pump needed for a dry sump lube system.

 

[RicksRides]

oops i mis quoted. It could be done Not sure what issues may come from it

 

[RicksRides]

So far it looks like pluggin the over flow holes, re-route the oil flow, drill hole high in case for ventilation,thread a fitting in and run hose from new hole to oil catch tank (with vented cap) remove bushing and machine case to take a bearing and seal instead. Im going sacrafice a set of cases to try this. I like this idea better then using 2 cases to make 1 engine. If successfull Ill offer rebuilt engines for sale with all machine work completed. Ill include intake and exhaust manifolds, carb, mag and oil filter set up. Ready to install

 

[wayne z]

So far it looks like pluggin the over flow holes, re-route the oil flow, drill hole high in case for ventilation,thread a fitting in and run hose from new hole to oil catch tank (with vented cap) remove bushing and machine case to take a bearing and seal instead. Im going sacrafice a set of cases to try this. I like this idea better then using 2 cases to make 1 engine. If successfull Ill offer rebuilt engines for sale with all machine work completed. Ill include intake and exhaust manifolds, carb, mag and oil filter set up. Ready to install

So, Where are you mounting the oil catch tank? Without using a crankcase scavenge pump like Harleys, BSA's ect with remote oil tanks, it seems like it would have to be lower than the engine crankcase.
I don't think those are actual oil overflow holes, I mean there's no oil level supposed to be in this type crankcase when the engine is running. There couldn't be.
There's a lot of air exchange going on in that cramped crankcase with that big piston and long stroke, so the oil emitted from the bearings is blown into a fog of droplets in there, and ends up collecting in the transmission case sump normaly. Too much turbulence in the crankcase for any oil level to build up. You may have some trouble with oil spitting from the crankcase vent.

Some aircraft engines have crankcase breathing issues, and they use simple design air/oil seperator can on the crankcase vent to re-claim vented oil droplets back to the sump. Aircraft Spruce sells a cheap one for use on expirementals.
I would think that a large hole tapped in the bottom of the crankcase might work. Then plumb it to a sump tank that's lower than the crankcase.

This is just my assumptions, might be better and easier ways to deal with it.
Im still playing with the idea of building a breather box/sump to cover the entire PTO flange. Would need no major mods to the engine.

 

[RicksRides]

Wayne those motor use both oil pump and splash oil systems the big oil holes serve 2 purposes ventilation and splashed overflow from the crank/flywheel assembly. Oil tank would btween the rear wheel and seat post overflow hose goes in top then piped back in oil filter assembly.. Enough of us working on this we will find a suitable method