Topic: 650 oil pump upgrade for 550

[BomberMann650]

Got an early 650's oil pump for the 550 engine build.
And there's one thing that doesn't quite match up.

Did I miss a memo about this mod?  There's a line behind the pressure sensor that doesn't match the 550 case.  Does that hole just get plugged?

The pump doesn't exactly fit in the cover chest.  But that was gonna become swiss cheese anyway.

[scunny]

I think B Waller did this on his 550 race bike.

[BomberMann650]

I think B Waller did this on his 550 race bike.

It was definitely discussed on this forum before.

But i may have hastened through the pages in my rush to "buy it now!"

So this is me, double checking here...before heading over to my hipo thread

[scottly]

Wasn't there a mod that used a deeper 650 oil sump, along with the longer pickup?

[grcamna2]

subscribed

[scunny]

I think he used the oil pan as well. hopefully he will chime in.

[flatlander]

Wasn't there a mod that used a deeper 650 oil sump, along with the longer pickup?

yes that's what brent did. searching his posts should bring up how he did it.

[BomberMann650]

Wasn't there a mod that used a deeper 650 oil sump, along with the longer pickup?

Sump...s...s..s.s...sump?  Not pump?

Fckme am I dyslexic?

[flatlander]

yes sump. for more oil capacity.
he may also use the 650 pump but that part i don't remember.

[bryanj]

I dont think the 650 pump fits, i think there is an extra oil output

[Mark1976]

   I did this last year on my '76 550F, I don't remember that being a problem, but you are going to have to shorten the oil pressure sending unit input lug. It was a little tall, wasn't able to install the countershaft/oil pump cover as the sending unit sat to high. I'm pretty sure there's a thread on plugging the oil port on the side. I'd disassemble that pump and inspect the rotors, many of these become worn and damaged over time. When I did the oil pump upgrade on my 400f, I went thru 3 or 4 cb750 pumps before I found a set of usable rotors. Most had rotor damage.

[BomberMann650]

Thanks mark.  I'll put the bayer aspirin down now.

I figured with the minimal wiring going onto a race bike, I would remove the pressure sensor altogether.
Should be able to drill, tap, and plug that extraneous line with a keeper screw.

[Mark1976]

   In 'cb550 track bike goes racing' thread (last page)addresses it. But I don't remember doing it on mine. There maybe 2 different pump housings I suspect.

[BomberMann650]

   In 'cb550 track bike goes racing' thread (last page)addresses it. But I don't remember doing it on mine. There maybe 2 different pump housings I suspect.

Part of that thread came up in the search.  But was focused on the sump and pickup swap.

[grcamna2]

I think B Waller did this on his 550 race bike.

It was definitely discussed on this forum before.

But i may have hastened through the pages in my rush to "buy it now!"

So this is me, double checking here...before heading over to my hipo thread

I hope Brent will speak on this.

[BomberMann650]

Update; clarification was found in the aforementioned thread.

Now to find a set of seals for the pump, clean it out, and plug it up.

Down the road I feel that extra volume would go well with a hair dryer.

[Mark1976]

I'm trying to remember when I did my swap, maybe when I  trimmed down the post that the sending unit threads into it may have blocked that passage off. 650 pump on the left trimmed down and stock on the right.
 CRS, can't remember s$%&... really sucks, but I can remember lunch from like 40 yrs ago like yesterday.

[Mark1976]

   There ya go, this is the piece of the oil pump that I trimmed off. I trimmed off at the mid point of that oil port (about 12mm) eliminating it and then reinserted the oil pressure sending unit. Ports not needed on the 550. The things we forget to throw out.