Topic: SOHC4 Engine top end oiler anyone?

[Terry in Australia]

I don't know about you guys, but over the years I've seen at first hand the destruction to the cam, rockers and valves in our bikes, brought about by oil starvation.

The oil to the top end is fed thru tiny "jets" that don't need much coaxing to block, and by the time you realize something is wrong, you've just killed your engine.

Now recently I've been hanging out with the "Muscle Bike" set over at the GS Resources website, and a hot item on a big 100+ BHP Suzuki DOHC engine is a "Top End Oiler" kit, which basically taps into the engines oil supply, and delivers additional oil to the camshafts to aid in lubricating and cooling all the top end components.

I've developed an oil cooler adapter for the big GS bikes which has an inbuilt top end oiler, and am receiving some excellent feedback from these guys on the merits of my latest version.

With that in mind, I've designed a simple SOHC4 top end oiler kit as an "optional extra" addition to my oil cooler adapters and cooler kits.

The "kit" will include a separate oil line tapped off the cooler adapter that will run up to a small manifold that will "split" the oil flow into the cam cover via a small seperate line to each of the four front threaded cam cover caps, which will be drilled and tapped for oil line fittings. No permanent mods will be required to the bike, it's all a "bolt on" affair, so can be transferred from one bike, to another. 

I've decided on directing the oil flow via the front cam cover caps as the exhaust side of the camshaft is the hottest side, so it should get the oil first. With this simple mod, oil will be sprayed around the cam cover with much more volume than the OEM design, resulting in reduced operating temps and (hopefully) much longer working life for the cam, cam tower bearings, rockers, valves, and valve springs. 

I'm going to go to a hydraulics shop tonight after work to pick up some parts, and on the weekend I'll make up a "prototype" so I can test it, and I'll take some pics. Cheers, Terry.

[scunny]

why do they have oil restricters in the first place ?

[bryanj]

To keep the bottom end pressure up

[754]

The size of the orifii.. just one more reason to make sure oil is clean and changed often..

 I would rather find bits of gasket in an oil change than find it blocking the cam supply orifice..

[Terry in Australia]

Very true Frank, it's been my experience that mechanics going cheap and trying to reuse old gaskets by applying liberal amounts of silicon sealant are the main causes of top end failure in our bikes, so running additional external lines might just help reduce the incidence of top end melt downs.

I might need to call on you to make me some thicker "custom" cam caps, so I've got enough "meat" to tap into for the fittings, if you're interested? Cheers, Terry.

[paulages]

terry- this is essentially what i'm doing on my 718 (and bwaller did on his 550), but i simply tapped one of the (pressurized) lower oil galley plugs, and rerouted to the top of the head. i'm still using in-line restrictors, but at least they can be easily removed and cleaned, unlike the stock jets and pathways. the 750 seems like it would be more prone to this problem though, as the pathways aren't as direct. this would be a great bolt on product IMO. i'd want to make sure that four separate lines were restricted enough to keep up bottom end pressure though.

[Steelo]

Terry you legend I'm up for a setup if the price is right having gone through this once already!!! The old tick tick tick suddenly riding on 2 cylinders then finding camshaft split into 2 is no fun!!! I like the idea of using the caps as inlet points.

[Terry in Australia]

Thanks for the feedback guys, and yes, I'll be using small ID line to keep the pressure up. I don't want to have to tap into the engine cases (even though there's nothing wrong with that) as I want to have the system as simple, and as portable between bikes as possible, that's why tapping off one of my oil cooler adapters seems like an easy way of doing it.

I'm going to mock it up this weekend with rubber hoses and brass fittings, and test it on my beeootiful K1 with the beastly engine, then take it to Enzed (hydraulic hose place) and get them to make me up some fancy stainless steel hoses and ends for my kits. The price will be dependent on what I have to pay for the hoses of course, but I'll do my best to keep the price down to "reasonably painless", ha ha! Cheers, Terry. 

[754]

Terry.. TTR on here already makes a stock looking cap.. may have to eliminate one machining op to allow thickness for threads.


 My gut feeling is too much oil up there will cause it to smoke, but you can probably tailor the amount of oil getting up there.

 A drawback I see is it is tough to get a clean install if you plumb into the tappet cover.

 Enlarging the hole in the stock restrictor should easily get more flow..

[Terry in Australia]

Terry.. TTR on here already makes a stock looking cap.. may have to eliminate one machining op to allow thickness for threads.


 My gut feeling is too much oil up there will cause it to smoke, but you can probably tailor the amount of oil getting up there.

 A drawback I see is it is tough to get a clean install if you plumb into the tappet cover.

 Enlarging the hole in the stock restrictor should easily get more flow..

Thanks Frank, but I don't think it'll make it smoke, it certainly doesn't on GS bikes, unless your valve guide seals are stuffed of course, in which case it'd smoke anyway.

We're only talking about a spray of oil here, not filling the entire rocker cover up. Yes the oil has to exit the rocker cover as well as enter it, but I'm confidant that the additional oil will easily drain back into the cases in the usual manner without any problems.

I suppose (but don't know with any authority) that opening up the OEM oil jets could work, but once again, my system is a simple 30 minute "bolt on" affair, and doesn't require pulling the engine and a partial top end strip down, as enlarging the oil jets will. Unless I was rebuilding an engine, (probably after replacing the top end due to a blocked OEM oil jet melting my expensive Honda parts) I wouldn't go to that extreme.

And at the end of the day, this system is going to increase the oiling points from two, as per the OEM design, to 6, with a lot more oil at the #1 and #4 ends of the cam, as opposed to most of the oil entering at the #2 and #3 portion of the cam and (hopefully) working it's way out to the extreme ends as per the original design.

So even in the event of one OEM oil jet blocking, it won't spell disaster for your SOHC4 engine, as it has for the last 39 years. Oh, and like everything I make, it'll also look really cool............ Cheers, Terry.    

[troppo]

you trying to get me into MORE trouble with SWMBO terry??

[paulages]

can't say it'll hurt in any way, but i imagine the cam journals being oiled by pressurized orifices is fairly important ? seems like this would play an important role in proper oiling. still, any oil is better than none...

[Terry in Australia]

can't say it'll hurt in any way, but i imagine the cam journals being oiled by pressurized orifices is fairly important ? seems like this would play an important role in proper oiling. still, any oil is better than none...

Are you talking about Franks suggestion to enlarge the jets mate, or have I missed something?

you trying to get me into MORE trouble with SWMBO terry??

Hey, it's only money Trop, and if you order one, you'll be the first "crow eater" with one on your bike, which will make you a hero in your state, and incredibly popular with the ladies, no doubt! (yeah, I'm working all angles here, ha ha!)

[troppo]

I dont need any more popularity with the ladies mate, what i`ve got is enought to keep me in the dog house
Having read about the problems that seem to be fairly common with the top end i thought this would be perfect preventative medicine, i dont want my old girl to die after i get her on the road because of a blocked gallery.
May have to rename the bike to the TIA special
 

[bwaller]

Paulages and a couple others of us have bypassed the top-end oil feed on the 500/550's completely by running external lines. For a couple different reasons, but not to add extra oil, just replace the original set-up. I have looked at the same deal for a 750 primarily to avoid oil leaks at those bloody o-rings. However it isn't as easy on the big four.

 I remember reading that with the sixties GP racers Honda considered "over oiling" would rob power and therefore spent considerable time designing the lubrication systems. Just a thought!

With the 750's the oil gallery that runs lengthwise through the cam towers SHOULD supply oil to six different points each tower, plus different splash lube points. As previously mentioned that restriction in the top-end feed quarantees the bottom end gets it's needed supply. In all honesty I've seen these restrictors blocked too, but increasing that orifice size is at the expense of the bottom end.

Terry I think adding a little extra oil might not be a bad thing and sourcing it from the cooler adaptor is the best approach so as not to rob supply from the bottom gallery.  But it doesn't take much oil I expect to make a difference. Are you planning just a mist from each inspection cap?  Any idea how much extra the pump can supply? Maybe an extra litre of oil, a larger resevoir and a much bigger rad than we've been using to cool might be a solution to decrease the extra heat of these bigger than 750 engines.

It sure doesn't hurt to try.



 

[Terry in Australia]

Paulages and a couple others of us have bypassed the top-end oil feed on the 500/550's completely by running external lines. For a couple different reasons, but not to add extra oil, just replace the original set-up. I have looked at the same deal for a 750 primarily to avoid oil leaks at those bloody o-rings. However it isn't as easy on the big four.

 I remember reading that with the sixties GP racers Honda considered "over oiling" would rob power and therefore spent considerable time designing the lubrication systems. Just a thought!

With the 750's the oil gallery that runs lengthwise through the cam towers SHOULD supply oil to six different points each tower, plus different splash lube points. As previously mentioned that restriction in the top-end feed quarantees the bottom end gets it's needed supply. In all honesty I've seen these restrictors blocked too, but increasing that orifice size is at the expense of the bottom end.

Terry I think adding a little extra oil might not be a bad thing and sourcing it from the cooler adaptor is the best approach so as not to rob supply from the bottom gallery.  But it doesn't take much oil I expect to make a difference. Are you planning just a mist from each inspection cap?  Any idea how much extra the pump can supply? Maybe an extra litre of oil, a larger resevoir and a much bigger rad than we've been using to cool might be a solution to decrease the extra heat of these bigger than 750 engines.

It sure doesn't hurt to try.
 

Thanks mate, and you're right of course, whenever I have a wonderful original thought like this, I always ask myself why someone hasn't already done it?

But like a lot of guys here, I was riding a shiny new Honda CB750 in the 1970's and I never saw anything like this system on sale as an accessory, so either I'm the smartest bloke in the world,( ) or it's not really necessary?

I'm of course leaning toward the former rather than the latter, but regardless, like you and a few others have already said, a little more oil surely can't hurt?

Oh, and to clarify my comment about the oiling points from the OEM system, yes, it's designed to oil at 6 points via the cam towers, but there are only two feeds from the bottom end, so block off one oil jet in the head, and you've lost half of them.

I've bought some fittings and rubber hose today, and tomorrow (Saturday in Oz) I'll machine up the adapter, manifold, some hose restrictors, I'll drill and tap some crappy old "chopper" inspection caps, and "mock up" the system on my K0 (albeit with no oil cooler, it's winter here) and take the bike for a decent ride, (if the rain gods are kind to me) then next week I'll get Enzed to make up some shiny braided stainless steel lines to replace the rubber. Pics tomorrow, I promise! Cheers, Terry.

[Jim F]

You know me terry
I,ll take one to put on the 836
as soon as I get that damn ARD working................
lol

good to here from you

Jim

[dusterdude]

im in

[voxonda]

Think I just might have one!

Keep up the good work, mate!

cheers, Rob

[Terry in Australia]

Woohoo! Thanks guys, I'm just finishing my breakfast, then I'm heading out to the workshop! Cheers, Terry.

[Terry in Australia]

Ok, the manifold is made and so are the "any position" brackets, but I need a couple more brass fittings for the "mock up" model and as it's Sunday here in Oz and the tool shop is closed, I'll take a break, spend my day off installing an engine in my Suzuki GS1000, and finish the top end oiler during the week. Stay tuned! Cheers, Terry.

[Terry in Australia]

Well I didn't get any more done on the TEO, but I did lift my GS1000 engine into my frame on my own, and surprisingly, my back is fine, even though I had to lift a CB750 engine off my shop trolley and put it back on afterwards, and lift the GS1000 engine on to the trolley, push it over to the frame, then lift the engine in, so all in all, I lifted 130+ pounds of engine four times in one afternoon, and I'm still feeling good, so that's great!

Anyway, I checked my email when I came in for dinner, and my mate John had sent me a couple pics of his blown CB750. He's been riding, building and racing this thing since the 1970's. I'm hoping he'll adopt me one day, and leave me this beasty in his will! Cheers, Terry.





 

[hector2800]

I've been through two cams recently on the same motor and noticed it is almost always the right hand cam end that goes. Reading your thoughts on this I intend to very slightly enlarge the corresponding oil restrictor, as the rest of the cam seems to be getting its fair share of oil. On inspection the restrictor appeared to be perfectly clean at the time of failure so unless the debris had fallen back into the oil ways there was no obvious blockage. Anyone got an endless supply of F2 cams handy?

[jonbuoy]

Great Idea - even better if it could replace the standard head oil paths - that would make it much easier for early head swaps for F2's and to get a leak free top end?  I remember my old ford OHC had an overhead oil rail spray system as the only source for cam lubing. 

[medic09]

Sounds like a good idea, Terry!

I had a similar idea set up on my SR500.  Pretty common on that bike, at least for folks who race or ride them hard.  Could even buy a kit on Ebay for a while.  I bet this'll work well.