Topic: 76 550 top gear rev problem

[FIREBLADE74]

plug 3

[FIREBLADE74]

plug 4

These all were ran with 1.25 turns out on air screw

[calj737]

So what needle clip position are you running, and post pictures of the Clear Tube test on all 4 carbs.

[Killer Canary]

Do you remember if you've cleaned the screen in the fuel tank/petcock?

[FIREBLADE74]

No clear test but the float are set to 22mm, which I verified twice already.

As for the petcock, I didn't do anything to.

What are the plugs saying?
Dirty tank?
Poor fuel delivery?

[calj737]

Theplugs are saying fuel starved. Do the Clear Tube. Setting float height by a measurement is okay, but Clear Tube is exact.

[evinrude7]

side question.  when you all do clear tube is it preferred on the bike or on the bench?  no diff?

[calj737]

No difference as long as the rack is level and fuel supply abundant.

[FIREBLADE74]

Bet! Thx calj.

What fuel lines do you suggest? Not for the clear test. Auto parts store doesn't have metric lines.

[DaveBarbier]

Next time just take a picture of all the plugs in one shot lined up 1-4 left to right.

What throttle position were you at? Jets are not RPM dependent. It has to do with slide opening, not RPM.

[DaveBarbier]

side question.  when you all do clear tube is it preferred on the bike or on the bench?  no diff?

It's easier to adjust the floats if you need to while it's on the bench.

[evinrude7]

Thank you sir

Sent from my LG-D850 using Tapatalk

[FIREBLADE74]

Next time just take a picture of all the plugs in one shot lined up 1-4 left to right.

What throttle position were you at? Jets are not RPM dependent. It has to do with slide opening, not RPM.

Will do on the pics but I wanted y'all to see the crazy discoloration.

I was at the stop throttle wise. Then I hit the kill switch and clutch.

I'm gonna reroute my fuel lines. Right now I have them sweeping over the top of the pods instead of coming thru the holes the lines came thru stock.

[turboed13b]

Air screw isn't going to do anything on top end. Set it and leave it.

Make sure boot clamps are tight first. Try raising the needles one notch. If that doesn't work jet up.

[FIREBLADE74]

Ok, problem 1!

Make sure your carbs are fully seated in the rubber boot, mine were partially on.

Noticeable pickup! Doing another chop, I'm thinking my plugs should show it being rich since my air mixture is 1.25. Notice hesitation in the low rpm range could be flooding.

I may need to resync carbs since they were synced with the half azz carb install??

[FIREBLADE74]

Plugs look nice and toasty.

I found that my exhaust was seriously loose, bolts backed out. This maybe the source for the hesitation.

Calj, what do you think?

[DaveBarbier]

Remember that the mixture screws only affect idle. I don't want you to think that they are an overall adjustment. Normally, you want to do a plug chop idling with a box fan on the headers for like 5 minutes. Then go to a chop at wide open throttle (while riding) and then work down (3/4, 1/2, 1/4, etc)

Glad there was an obvious issue, that's always nice to find. Hopefully it's a lot closer.

[FIREBLADE74]

Dave,

It looks good so far! I'm going to tighten up that exhaust and sync again.

But in all actuality I think I'm expecting too much from this bike, lol.

[BomberMann650]

50-ish hp can be a lot of fun if ya know how to use it!
Even the professionals take corners at 35mph.

Exhaust leaks suck

[FIREBLADE74]

50-ish hp can be a lot of fun if ya know how to use it!
Even the professionals take corners at 35mph.

Exhaust leaks suck

Its fun but coming from a 1000cc bike, it feels like something is wrong, lol.

[BomberMann650]

These were smooth running motors for the time.  Salesmen would balance coins on the fins of a running motor.  If the points timing and vacuum sync are off, it will run rough.

I've been passed by liter bikes like I was standing still..  even at 4th gear redline (85mph-ish)

[FIREBLADE74]

These were smooth running motors for the time.  Salesmen would balance coins on the fins of a running motor.  If the points timing and vacuum sync are off, it will run rough.

I've been passed by liter bikes like I was standing still..  even at 4th gear redline (85mph-ish)

Lol, they will haul azz!!

[RAFster122s]

It never is going to have the acceleration or speed of a Liter bike... It is the audio and the feedback the bike gives you is so much different than a modern bike. Their aesthetics are what draw many to them. They have a lot of character and soul. The Carbs are more of an auditory thing when not in an airbox as well as the tappets and chain and the general exhaust note is so much different. Exhaust being easily changed...  The big bikes and the sport bikes are like riding a rocket sometimes.  Not quite Busa level but they do not slouch in any regard.

If you are coming off a Fireblade Liter bike it has what 120hp? or more?  I have no idea...just a swag. 

Sometimes going slower can be fun...especially when you are with bikes of similar limited hp and are dicing it up on a track. You don't have to go fast to have fun.  Sometimes even going slow you have time to look around and enjoy the experience.  It is that way on a 70cc Passport.  You are only going to be going 35-40mph and in city traffic drivers are gonna hate you but out away from city traffic where you don't have that pushed feeling behind you, you can enjoy the ride and have more time to scan the surroundings if there isn't much traffic. TOTALLY DIFFERENT experience than zooming down the road.

The small bikes around 100-150cc, old vintage bikes, are often called Tiddlers and lots of folks in the NE love to get together for Giros with them and just out for a fun ride together. They can be lots of fun. 

The guys on their sport bikes blasting down the road at 100-120 to 160 or so are there for the thrill and they are really a risk to themselves and their fellow riders as things happen so fast at those speeds. Naturally you are not operating your bike at those speeds in heavy traffic.  You aren't making videos to show on the net of your bike doing 200km/h or 120-160 in traffic like some duffus' in Ontario and the like that the police decide to track down and prosecute.
Or acting like the hooligans in gangs of riders stunting on the highways in large packs of riders and basically running roughshod over any laws and traffic by sheer numbers and disregarding all laws depending upon the numbers overwhelming the police's ability to arrest them.  That some of their group will fall victim and you will laugh about it....
 

[FIREBLADE74]

So true!

I do enjoy the low power, especially on those back roads. It seems that you can look around more be more relaxed but on that blade it wants to go fast and that's actually where it likes to be, slow riding it does not like, handling suffers.

I'm going to tighten this exhaust, adjust this clutch and ride it like I stole

[calj737]

Plugs look nice and toasty.

I found that my exhaust was seriously loose, bolts backed out. This maybe the source for the hesitation.

Calj, what do you think?

I think it was always pays huge dividends to cover all the basics when dealing with performance issues. Don't get crazy tightening the exhaust. There's copper crush gaskets (o-rings) in the head that ought to be replace. Apply too much torque attempting to seal up the exhaust, you'll shear the exhaust stud. Get 4 new ones, release the exhaust, dig out the old ones, then install the exhaust and be certain everything is buttoned up.

A WOT chop and an IDLE chop would serve you well.