Topic: 1977 -78 750f supersport high miles ?

[HAULINHONDA]

who has the highest miles on 77-78 cb750f2 ??what do you have on yours without rebuild???keep it under 90>>>>>

[seanbarney41]

If you have a 77/78F that didn't need valve guides by 30,000 you are doing good.  Mine smokes like a 2 stroke and uses a quart every 3-400 miles at 28,000...I still love it and it will get fixed.  Just not right now. 

[drumstyx]

If you have a 77/78F that didn't need valve guides by 30,000 you are doing good.  Mine smokes like a 2 stroke and uses a quart every 3-400 miles at 28,000...I still love it and it will get fixed.  Just not right now.

An expensive job, unfortunately. My '78K needed everything, so I got the spa treatment from MRieck. Not cheap, but the problem is resolved completely with such a rebuild. It won't have a similar problem ever again.

[Don R]

 There are F models that have survived for hundreds of thousands but they were meticulously maintained with 20W50 oil.

[martin99]

There are F models that have survived for hundreds of thousands but they were meticulously maintained with 20W50 oil.

What oil should I use in my 750?











 

[seanbarney41]

There are F models that have survived for hundreds of thousands but they were meticulously maintained with 20W50 oil.

yes Don F0 and F1's...have not heard of F2 and F3's lasting without fixing the big valve/valve guide issue, totally different engine

[HAULINHONDA]

NICE

[HAULINHONDA]

WHAT BRAND OF OIL AND HOW LONG BETWEEN CHANGES 20-50?  THANKYOU

[Stev-o]

There are F models that have survived for hundreds of thousands but they were meticulously maintained with 20W50 oil.

What oil should I use in my 750?

What's the best oil on your side of the pond, Martin?!

[martin99]

There are F models that have survived for hundreds of thousands but they were meticulously maintained with 20W50 oil.

What oil should I use in my 750?

What's the best oil on your side of the pond, Martin?!

Whatever is the cheapest Stev-o!

At the moment it's ipone 20/50 4T mineral, French I think but it's great stuff, I can even find neutral sometimes 

BTW, my F2 valve guides needed replacing at 23K.

[Old Scrambler]

Just tuned and rebuilt the brakes on a '77 F2...........with 56xxx on it. Sometimes it smokes on startup........and sometimes not. Otherwise it runs very strong and has nice original exhaust..........but not for me.........just sold it on ebay to someone from Mexico ...........The buyer is aware of the need for new valve guides and seals.

[1978CB750SS]

My CB750F bike says 1977 on the frame tag, title says 1978. I understand it was sold as a 1978, but does that make mine an f2? or an F3?
I have 26800 on it now but the PO said he had taken top end apart when he got it as the engine was seized. I asked if it had new
rings or anything while apart, he said "No, everything looked good, I just cleaned it up and put it back together" at least he was honest about the
tear down and stuck engine. The motor and frame is very clean and looks like he had the engine out. I did have it running ( crappy) but all
pressed in jets were plugged and carb was (is) missing parts. It did blow some smoke but it wasn't firing on all cylinders. #1 pipe was not hot.
 I will not know if she's a smoker/oil chugger until I get it running right. I'm hoping to get it together this summer and enjoy some CB time while the season lasts.

[Airborne 82nd]

My CB750F bike says 1977 on the frame tag, title says 1978. I understand it was sold as a 1978, but does that make mine an f2? or an F3?
I have 26800 on it now but the PO said he had taken top end apart when he got it as the engine was seized. I asked if it had new
rings or anything while apart, he said "No, everything looked good, I just cleaned it up and put it back together" at least he was honest about the
tear down and stuck engine. The motor and frame is very clean and looks like he had the engine out. I did have it running ( crappy) but all
pressed in jets were plugged and carb was (is) missing parts. It did blow some smoke but it wasn't firing on all cylinders. #1 pipe was not hot.
 I will not know if she's a smoker/oil chugger until I get it running right. I'm hoping to get it together this summer and enjoy some CB time while the season lasts.

Go buy the number on the engine not the frame (for what you want to know). These carbs don't like missing parts. Just what parts are missing?

[Handlebar]

I was hammering on my 78 last fall and something came loose on the right side. 12,000 miles. I have not tore into it yet. Time will tell. Wish me luck.

[1978CB750SS]

My CB750F bike says 1977 on the frame tag, title says 1978. I understand it was sold as a 1978, but does that make mine an f2? or an F3?
I have 26800 on it now but the PO said he had taken top end apart when he got it as the engine was seized. I asked if it had new
rings or anything while apart, he said "No, everything looked good, I just cleaned it up and put it back together" at least he was honest about the
tear down and stuck engine. The motor and frame is very clean and looks like he had the engine out. I did have it running ( crappy) but all
pressed in jets were plugged and carb was (is) missing parts. It did blow some smoke but it wasn't firing on all cylinders. #1 pipe was not hot.
 I will not know if she's a smoker/oil chugger until I get it running right. I'm hoping to get it together this summer and enjoy some CB time while the season lasts.

Go buy the number on the engine not the frame (for what you want to know). These carbs don't like missing parts. Just what parts are missing?



I found a spring at Ace hardware for the accelerator pump, I am awaiting the tiny o rings and washers for the air mix screws. I have no airbox on it as of yet.
 I  have a set of round top carbs and airbox that came with the round top set of carbs. Looking at both I see the ss carbs are slightly bigger at the air entrance side and probably the other side too.. I suppose the box will fit, just need to switch out the boots on both sides.. The boots on the engine side are cracked also. One has a kind of big crack.
 I'll need the filter for the airbox,a new chain,put the new tires I have on the bike and re-wire the front blinkers as someone was in there , they changed the blinkers to these small ones and they do not blink, they stay on constant. I like the big factory lights, I want people to see me making a turn. lol Also all the rear lights had been disconnected. I also have the plastic fender and little trunk compartment plastic that needs to go back under the seat.Other than that this puppy will be rolling and I will be a happy CB guy. I never was a "Buy and Ride" kind of guy. More of a buy and fix it upper. This bike will the best I ever had. Oh ya, the brakes stick when I touch them, if I tap the calipers with a rubber mallet, they unstick and roll again. I guess I need to clean up the calipers. All 3 of them.

[1978CB750SS]

I was hammering on my 78 last fall and something came loose on the right side. 12,000 miles. I have not tore into it yet. Time will tell. Wish me luck.

Good luck Sir. I hope it's something small. It was probably that keeper problem they mention. I hope you shut it down in time to minimize repairs.
I have 26.000 on mine. Haven't actually drove it yet. It was (and still is) a project. lol

[madmtnmotors]

WHAT BRAND OF OIL AND HOW LONG BETWEEN CHANGES 20-50?  THANKYOU

Any motorcycle specific oil and per the manual every 1,500 miles. Bel Ray 4T 20/50 mineral oil has been my go to lately in my drag bike.

Takes a while to rack up 1,500 miles 1/4 mile at a time... 

[Geeto67]

I bought my 1978 F in 2006 with 36,000 showing on the odometer which was broken. I rode that bike regularly on my commute from 2006 to 2011 before my fiberglass dunstall tank started to delaminate. It has never smoked as long as I have owned it. I do not know if the engine was ever gone through but it runs stronger than any cbF I have owned (it's as fast as my 79 DOHC was/is). For all I know I could be riding a time bomb as I figure the mileage is about 45-50K now. This bike did not live a charmed life - it was an NYC rat for most of it's life and the guy I bought it from had been street racing it and beating on it hard.

I had another 78F that had less than 10K miles on it before the valve guides let go. The engine let go shortly after and someone on here built a nice hot rod out of the chassis.

for any used vehicle I have owned that was going to see high mileage - oil is the most important part. I try to run synthetic in all my bikes but for those that have run dino oil I usually have to walk it through 2 cycles of semi-synth to keep seals from weeping and gaskets from popping. oil change once a season whether it needs it or not.