Topic: 5 Liters to go 50 Kilometres??!

[PGF550F]

Just getting my 77 550F out and commuting to work with it. Best way to get to work btw!!
Topped up the tank with reg gas 87 octane and headed off to work. ~ 50 km highway ride. Got to work and parked for the day. Stopped at the gas station to fill it up and it takes 5 Liters to fill it??!

Bike has stock air box with oiled UNI foam filter and new carb to Airbox boots and clamps.  4-1 stock exhaust header with an unknown manufacture baffled pipe. ~23000km and compression is about 150lbs in each cylinder. Petcock turned off for the day and no noticeable fuel leaks from carbs during the day. Could the motor really be digesting that much fuel? (~25mpg). Bike starts and runs well but pops a bit on heavy deceleration/ downshifting.  Carbs have been cleaned stock jets, idle mixture screws at 1.5 turns. tires new and properly inflated. Chain adjusted and lubed ~200km ago.

I pulled all 4 plugs when I got home and they all looked fairly dark sooty blackish/grey but still some lighter colour on the insulator. I have to be running horribly rich with my fuel consumption.
I'm going to pull the air filter before I head out tomorrow and see if I can notice an improvement. I used BelRay foam filter oil. Maybe it's not letting enough air through or I over oiled it.

Any other thoughts what it could be? Poorly set timing?

[flybox1]

Please detail your carb jetting, IMS setting, exhaust configuration, and air filter type.
(You mentioned you added oil to the air filter...SHOULD it be oiled?  Is it a stock paper element you have oiled?)

[Don R]

My 750F1 had high floats that caused the range to be low.

[Bankerdanny]

Please detail your carb jetting, IMS setting, exhaust configuration, and air filter type.
(You mentioned you added oil to the air filter...SHOULD it be oiled?  Is it a stock paper element you have oiled?)

He said it's a Uni filter

[Deltarider]

Probably the foam filter, either overoiled, or simply not fit for the task. Why you guys all turn to #$%*ty filters when you still can have the real thing, is a mystery to me. There isn't an obstruction like a cloth under your seat blocking airflow? Deteriorated and so leaking O-rings around the main jets can also be a cause.

[flybox1]

+1 to over-oiled.

[PGF550F]

Jets are stock keihin brass. 98 Main and 38 Pilot Jet. Scews are solid tipped and at 1.5 turns out.

I bought the UNI filter on recommendation of HondaMan here on the forum as the bike had NO filter when I got it. I understand that the stock paper element may be available but I think the UNI is a good filter, I just may have over oiled it.



I rode to work this AM after pulling the filter out and it seemed to run better(more power with less throttle) and more consistent. I should have mentioned that I have done the 3000 Mile service and I do have the factory service manual(downloaded from here). NOS points and condensors, new plug wire, NGK plug caps and spark plugs.
 

I guess Ill have to clean and re-oil(lightly this time) the filter and try that out. Ill pull the plugs and check them as well and note if my fuel consumption has changed.

[flybox1]

You might want to snug up that exhaust, too 

[Deltarider]

I always recommend the genuine Honda filters. They do not restrict, filter way better than foam and can be serviced within seconds. A filterexpert informed me that when airfilter A filters out 99,8 % of the particles and airfilter B 99%, enginewear with B is already fourfold. 
On my CB500 the genuine Honda airfilterelements last at least 18.000 kms and do not detoriate over time. That's not bad for a filter that costs only around € 20,-. http://www.davidsilverspares.co.uk/parts/by-part-number/partnumber_17210323030/
Foam filters may do fine on lawnmowers.
Some may find it hard to believe but as a matter of fact paper filters get better in use. For this and more info: http://forums.sohc4.net/index.php?topic=98901.msg1102737#msg1102737
Can't believe so many want to risk it with Unifoam filters or whatever they're called, filters that already are inferior fom the start. None of the genuine Honda filters I've used, served less than 18.000 kms. As a matter of fact I still keep them in my basement as they still are not clogged and so filter at their best. And the best thing is: I can change my airfilterelement within 10-12 seconds and that includes opening the seat, removing the tooltray, etc. And time, my friends, is the only thing I cannot make extra of. So why would I spend precious time on oiling, getting my hands dirty and then have to worry: did I oil too much, too little? Good Lord, what is it that you guys overthere who back then could buy our Honda bikes for far less $$ than they've costed us, ride on gas that is only 25-30% of the price we pay here, are so tempted to buy inferior parts. I just don't get it.

[PGF550F]

You might want to snug up that exhaust, too 

Ha, just looked at the photo, that is just a chrome cover hiding the rusted surface finish of the header/muffler junction.

Could vacuum leaks also cause it to run rich? or do Vac leaks typically make it run lean? the Manifold to head O rings are still the originals and are apparently a common source for poor sealing.

Also, how long do you have to run or how hot do you have to get the plugs for them to self clean?

Never guessed I would get flamed for using a UNI foam washable/reusable filter... maybe I should have spent the $50 dollars on a stock honda filter element. Ill keep at it with a clean, lightly oiled foam filter...or convert to pods and pull all my hair out.

[flybox1]

Vacuum leaks would make you lean.
Many use the Uni filters, but yes, oiling is easily overdone.
Can you wick out of it with some paper towels?
Paper filters are under $20

[PGF550F]

I live in Canada, so unfortunately the stock Honda paper filter elements are around $50-100 here. The UNI filter is re usable and less $$ than that, although I maybe got a little heavy handed with the oil. The belray foam filter oil I used was fairly sticky blue stuff, I might try wick it out but I think I'll re-oil with UNI branded oil. The shop didn't have any when I got the filter so I used what I could find. Lesson learned.


Sent from my iPhone using Tapatalk

[Deltarider]

Paper filters are under $20

For a good imitation, yes http://www.davidsilverspares.co.uk/CB550F-SUPER-SPORT-1977-USA/part_70097/ but genuine Honda is a bit more. http://www.davidsilverspares.co.uk/parts/by-part-number/hpart_17210390003/ But... no extra costs of oil, no messy hands, fitted within 12 seconds and not having to think of it for the next 18.000 kms. I suspect some want to make things as complicated as possible and rather tinker than ride.

[flatlander]

guys, for what it's worth, last time i had my 550 on the dyno i tested a uni foam filter (correctly oiled) against the honda paper filter. not only is the honda filter cheap and it does its filtering work, it also flows better producing significantly more power.

uni is red, honda is blue:

[Deltarider]

Great info, Flatlander and isn't it great that after 40 years the genuine filter is still available?

[flatlander]

yes i wanted to know what all that hype is about and after seeing these results, it's original filter for me, all the way!

[BomberMann650]

Not to detract from convo.  But PGF - i really dig the tan seat.

[mrbreeze]

I live in Canada, so unfortunately the stock Honda paper filter elements are around $50-100 here. The UNI filter is re usable and less $$ than that, although I maybe got a little heavy handed with the oil. The belray foam filter oil I used was fairly sticky blue stuff, I might try wick it out but I think I'll re-oil with UNI branded oil. The shop didn't have any when I got the filter so I used what I could find. Lesson learned.


Sent from my iPhone using Tapatalk

You used what you could find to oil the filter? So what was it you used?

[PGF550F]

I used bel ray aerosol foam filter oil. It has a reputable name so I wasn't concerned about it initially.

http://www.belray.com/bel-ray-foam-filter-oil-spray

I was told at the shop that so long as the oil was for foam air filters that it would all do the same thing. I guess you can't believe everything you hear.

Flatlander that Dyno graph along with all the others negative comments about the oiled UNI filter has me seriously rethinking my choice, it seems pretty clear that the OEM paper lets the engine "breathe" better.

I'll see if I can tune it with the cleaned lightly oiled filter I have and get the fuel consumption somewhere I would consider reasonable and if not I guess I'm ordering an OEM to eliminate that as the possible cause.


Sent from my iPhone using Tapatalk

[PGF550F]

Not to detract from convo.  But PGF - i really dig the tan seat.

Thanks for the positive feedback, I get mixed reviews some people have said they like it but others hate it, ideally I was hoping to get a black replacement cover but I think I'll run this one till it wears out. With as many miles as I put on in a year that will likely be a while! It's in great shape and complete with chrome trim and all.


Sent from my iPhone using Tapatalk

[754]

Do our know what your needle  clip position is?

[PeWe]

Ignition OK, not too late? (Retarded)

[chewbacca5000]

They may run rich, but they still have their place.  The individual filters are very easy to take on and off.  The 550 airbox can be a real PITA.  The 750 o so easy.

Also not a whole lot of messing with jets as it runs half choked anyhow. 

[scottly]

guys, for what it's worth, last time i had my 550 on the dyno i tested a uni foam filter (correctly oiled) against the honda paper filter. not only is the honda filter cheap and it does its filtering work, it also flows better producing significantly more power.

uni is red, honda is blue:

It would be interesting to see the results without a filter at all, retaining the stock airbox.

[PGF550F]

Needles are on the second grove from the bottom.  Switched to 2 turns out on the idle mixture screws and no filter and burning waay less fuel.
I'll hopefully have a chance to clean and re oil the filter tomorrow and test that. Clearly running too rich before because removing the filter made it run more efficient.


Sent from my iPhone using Tapatalk