Author Topic: 1976 CB550F - making it good, one step at a time (Read 121034 times)

strynboen · « **Reply #375 on:** February 24, 2016, 08:34:44 AM »

no..i have dp 300..its like sirup..thik and makee long "tailes"..its just to gluey. and thik.to use .(.mine is a old tube..so it can be too old and dryed up a bit...)
think it are more like this..that i use..(.flange tætning)
http://shop.berner.eu/dk-da/service-center/p/42437-flydende-pakning-tube-50-ml.html?article_id=42437

its easy to open a engine even it have sit for some days..nice if you have forgotten somthing inside...and Work fine in a kombinasion vith paper gaskets..

flatlander · « **Reply #376 on:** February 24, 2016, 09:33:44 AM »

tusind tak!

flatlander · « **Reply #377 on:** April 03, 2016, 01:35:10 PM »

there's one thing that i didn't finish last year, and that's the clutch mod to take 8 fibre plates.
over the winter months i did some more digging and experimenting. i found out that the steel discs of the 500 are about 0.9mm thinner than the 550 ones, but fit otherwise. so by skipping the damper plate, adding an additional fibre plate and combining steel discs of the 550 and 550, it's possible to create the right amount of free space in the basket.

what i have now installed is using 7 of the regular fibre plates, 1 top fibre plate with the wider tabs, 3 steel discs from the 550 and 4 discs from the 500.

with no springs installed, it looks like this in the basket:

this works fine, not clearance problems like i previously had. i think the amount of free space can be reduced further but that's for another round of experimentation. for now, this is good.

more info on this mod is in this thread: http://forums.sohc4.net/index.php/topic,145565.25.html

RAFster122s · « **Reply #378 on:** June 11, 2016, 02:28:38 PM »

Looks good and nice score on the K3 cam cover. How much did you have to pay for it if I may ask? Was it a SOHC/4 transaction or ebay or otherwise. I need to find one for my '74.

David

flatlander · « **Reply #379 on:** June 12, 2016, 01:26:04 AM »

i got it from a guy i know here in the netherlands, who has a small warehouse full of stuff. his website: http://www.blauweplaat.nl/

i paid 80 euros for the cover (incl. rockers, excl. tach gear house) if i remember correctly.
ebay or a wanted ad here may have been cheaper but i wanted it quickly and when he had one, just took it. he's got tons of stuff so if you're stuck he could probably ship you one.

RAFster122s · « **Reply #380 on:** June 14, 2016, 03:09:28 PM »

Thanks flatlander, i imagine it would cost a fortune to have it posted from the Netherlands.

The Nether Lands was a great album from an artist named Dan Fogelburg about 30-40 years...enjoyed his music. Never visited the Netherlands, the photos show it to be a beautiful place with great people. Everyone I have met and worked with over the years from there has been a positive experience. Not true of all countries I have worked with...used to do a lot of international business in an earlier career I worked in for about 20 years.

flatlander · « **Reply #381 on:** June 14, 2016, 10:22:22 PM »

don't know that album, must look it up now.
i've lived in a few different countries in europe after my parents escaped from what was then communist hungary. germany, switzerland, sweden, ireland. dutch people i met were always a good experience as you say. about 12 years ago we moved to amsterdam from ireland with my girlfriend, and we're still happy here.

flatlander · « **Reply #382 on:** October 15, 2016, 02:02:15 PM »

it's been a while... everything's pretty good except i noticed that sometimes, when trying to rev past a point between 8 and 9k rpm, it holds back. not always, and when it does, then i can drop back to a lower rpm, roll on again, and sometimes it then goes all the way up. also up to that point it runs great and very strong.

my first guesses were jetting or the restrictive OEM exhaust, but i couldn't really put my finger on it, especially as it was not completely consistent.

today i took the bike to the dyno for some troubleshooting. it showed this behaviour there, too.
tried with open gas cap to make sure it wasn't a venting issue - no change. tried with gas from a different source to make sure it wasn't fuel delivery - no change. checked spark through the full rpm range - it was good. checked voltage - also good. checked with airbox cover removed - no change to the behaviour.
and when it did go all the way to redline, the A/F mix was good.

now we eliminated a range of possible causes but still haven't found the source of the problem. mulling it over, over a cup of coffee, we thought it's worth trying with open exhaust just to see if it will solve it.
but... i've never actually had the muffler off the collector box because it didn't want to, and i didn't want to force it. that could be an indication that there's more corrosion on the inside then the outside looks make you expect, which may result in even more restriction. i didn't want to take it off now in case it's so bad that i couldn't get it back on. riding home without muffler wouldn't have been a good idea.

so now i'll be searching for someone who can lend me a complete exhaust system to try with. that should prove if my current OEM muffler is toast or if i need to look somewhere else.

calj737 · « **Reply #383 on:** October 15, 2016, 03:56:28 PM »

It's a shame you live across the pond; I have a MotoGP 4:1 sitting on the shelf awaiting installation in the next several months. Would love to see the change on the Dyno with it versus your stock system (and to see if it solves your issue).

RAFster122s · « **Reply #384 on:** October 15, 2016, 09:56:28 PM »

I have a excellent condition made in Japan 4-2 system that is with reverse megaphone exhaust... I expect it to be pretty quiet. Previous owner didn't like it and went with a different exhaust. I have no idea where he got it or the manufacturer...

If you didn't need to have gaskets to remove and remount the muffler it should be possible to figure out how restrictive the muffler is using a vacuum that can also blow to figure out if your exhaust is restrictive with flow from the vacuum. If the . If it is pretty free flowing the increased frequent starts making a much higher or lower pitch when you try to put the output nozzle

strynboen · « **Reply #385 on:** October 16, 2016, 02:44:02 AM »

have you put new springs in the sentifugal regulator..if they are to soft..it gives full advance ,a bit to erly..it can give that symptom...

flatlander · « **Reply #386 on:** October 16, 2016, 06:45:46 AM »

cal:
i would've loved to try that! although, if my stock system is rotten then it wouldn't be a representative result.

RAF:
if i need a different exhaust (which looks like i do) then i haven't made up my mind yet on which way i'll go. whereabouts are you? sending one over from the US would be a bit crazy i think.
i won't take off my stock muffler just yet, not without having a replacement ready. i fear i may not get it back on in one piece if i do!

stryn:
i have a boyer ignition, no more mechanical advance. we checked: it sparks happily and accurately.

question:
notice those perpendicular lines on the muffler below? i've always had them and never thought anything of it, but now i wonder if this is normal, or maybe a sign that it's corroded on the inside? i figure it could be the dividers of the chambers that become visible.
maybe someone has a stock 550F muffler and can check?

calj737 · « **Reply #387 on:** October 16, 2016, 07:10:17 AM »

I would speculate that is the result of the baffle being welded to the inside and the heat effected zone is internal, and not reaching the exterior in that area.

Stev-o · « **Reply #388 on:** October 16, 2016, 07:29:10 AM »

Hey FL - my 550F stock exhaust also has those same lines. This bike now pulls strong up to 9K, was a different story a year ago and turned out to be carbs (PO installed aftermarket kits)

I'm doubting exhaust is the issue.

flatlander · « **Reply #389 on:** October 16, 2016, 07:47:23 AM »

ok so there's hope still for the exhaust. if i get my hands on a different one i try it anyway as it's a relatively quick and easy test.
carbs parts looked all stock to me when i had them apart, at least the jets. hard to tell with the other stuff. if the exhaust doesn't fix it i'll have a closer look.

bwaller · « **Reply #390 on:** October 16, 2016, 08:23:05 AM »

Pretty sure the visible "swelling" showing on the muffler is internal rust. That doesn't necessary mean you should toss it, just that it corroded from excessive moisture at some point in it's past. That often showed itself on long 400F mufflers too.

flatlander · « **Reply #391 on:** October 16, 2016, 09:25:14 AM »

that was my suspicion, too. no worries, i won't toss it that easily. first i try if my funny problem goes away with a different one. if it does not, then i know i need to look somewhere else, like the carb parts as was suggested.

flatlander · « **Reply #392 on:** October 17, 2016, 11:15:06 AM »

i took the bike to work today, to another office of my company which is a couple hours riding on the highway. guess what? it ran like a scalded dog! it willingly revved north of 9k in 4 and 5. i ran it at 9.5 and 10k multiple times.

as good news as this is, i'm puzzled. it's a couple of degrees colder today than saturday when we did the testing, and cooler than all summer. that's the only difference that i can think of. the next few days stay cooler as well so i can try again how it goes.

Stev-o · « **Reply #393 on:** October 17, 2016, 04:35:19 PM »

Did you refuel?

bwaller · « **Reply #394 on:** October 17, 2016, 05:29:03 PM »

It could be that it was too rich previously. Cooler, more dense air needs a bigger jet.

flatlander · « **Reply #395 on:** October 17, 2016, 10:46:15 PM »

Quote from: Stev-o on October 17, 2016, 04:35:19 PM

Did you refuel?

yes.

Quote from: bwaller on October 17, 2016, 05:29:03 PM

It could be that it was too rich previously. Cooler, more dense air needs a bigger jet.

or like the others said, that the carb internals need more thorough cleaning?
A/F is about 12.7:1 at higher rpms at 21C.

strynboen · « **Reply #396 on:** October 19, 2016, 07:43:12 AM »

i think the air is more dence"holds more vater/air..and is a bit cooler too..its bind oxigen in the intake air..so the engine breath more burnabel air..a good seson..a shame the road grib is gone at the exatt same time

flatlander · « **Reply #397 on:** October 19, 2016, 12:20:23 PM »

yeah so those who put their money on jetting may be on to something. i need to give this another try in cooler conditions.
won't be able to deal with this very soon now as my partner had a death in her family and is gone now for a week and i'm holding the fort on my own.

Trad · « **Reply #398 on:** October 19, 2016, 07:18:30 PM »

Enjoyed catching up on this one. +1

flatlander · « **Reply #399 on:** October 20, 2016, 01:16:42 PM »

thanks man! i still have your cam here. during the dark and cold season i'll drop it in and see how it does.

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Author Topic: 1976 CB550F - making it good, one step at a time (Read 121034 times)