Author Topic: Gentlemans Express Cb550  (Read 20067 times)

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Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #75 on: July 25, 2016, 09:38:21 PM »
Right Tews. 4th position or groove on the needle. I see that the stock main is 100 which I thought was 98 stock. But I don't see how moving up to a 100 will cure my rich problem.
I'll start by pulling the carbs like Bwaller says, then I'll remove foam from the air box.
I'll replace the foam with a finer mesh.
Would changing the needle position be the next step?

Offline bwaller

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Re: Gentlemans Express Cb550
« Reply #76 on: July 26, 2016, 04:42:30 AM »
Cam I suggest just pulling the airbox and running open carbs to see if it goes lean.

Offline Tews19

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Re: Gentlemans Express Cb550
« Reply #77 on: July 26, 2016, 04:54:32 AM »
Plus one to what Brent suggested.

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Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #78 on: July 26, 2016, 07:50:57 AM »
Will do today guys. Thanks!!
Hypothetically what happens if it doesn't lean out?

Offline bwaller

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Re: Gentlemans Express Cb550
« Reply #79 on: July 26, 2016, 09:14:07 AM »
If it doesn't, call it Houdini.  ;)

Offline bwaller

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Re: Gentlemans Express Cb550
« Reply #80 on: July 26, 2016, 09:53:15 AM »
Jokes aside, to start the process it can be faster to go to extremes in jetting to begin. Too rich first attempt, pull the airbox to be sure it goes too lean then work backwards.

Did you say the top & sides of the airbox are blocked so no air except from the bottom?

Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #81 on: July 26, 2016, 10:21:59 AM »
Bwaller: they were blocked. I removed the metal that was blocking them. And I just pulled the foam out as well. This now just looks like Vstacks with a box attached. Besides a metal grate around the box there is now no blockage at the intake.

Offline bwaller

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Re: Gentlemans Express Cb550
« Reply #82 on: July 26, 2016, 12:17:49 PM »
Oh ok, just try it like that.

Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #83 on: July 26, 2016, 01:04:12 PM »
Well still no luck. I have to travel a few blocks to get to a road where I can actually do a proper plug chop. But I think the plugs are fouled already by the time I get there.
Still showing rich and sooty.
In an effort to stop asking dumb questions any more, and save you guys the energy answering them, I booked some dyno time this Saturday. I put in a call to Paul from Fast by Gast which is right up the street from me and he set me all up!
Plus we can get some Hp numbers.
Bottle of whiskey for the closest guess!

Offline Tews19

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Re: Gentlemans Express Cb550
« Reply #84 on: July 26, 2016, 01:32:45 PM »
If carbs are off you will have 37 first pull, middle pull 44hp, and third pull 38hp...

This is weird TBH. I can't see how you are rich with 98 mains... scratching my head.
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Offline calj737

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Re: Gentlemans Express Cb550
« Reply #85 on: July 26, 2016, 01:53:37 PM »
Might want to fully inspect your ignition before getting to the dyno. Would be a shame to waste the time and money to tune carbs and find its spark issues.
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Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #86 on: July 26, 2016, 02:06:40 PM »
Good advice Cal. Luckily there isn't a clock running on the dyno time.

Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #87 on: July 26, 2016, 02:53:24 PM »
Same Tews. All I can really think of it doesn't like the stock needle position and it's too rich down low, oil blow from the rings still settling in, or weak spark. Timing is spot on. We will be tuning between dyno pulls so I hopefully we will see numbers a lot higher than you are mentioning lol.

Offline Tews19

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Re: Gentlemans Express Cb550
« Reply #88 on: July 26, 2016, 03:08:41 PM »
I have the 605 big bore kit like you. 650 cam, stage 2 head work from MReick and had 44hp on my best pull. Motogpwerks exhaust as well.
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Offline bwaller

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Re: Gentlemans Express Cb550
« Reply #89 on: July 26, 2016, 04:04:41 PM »
Are they oil fouled?

Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #90 on: July 26, 2016, 04:26:48 PM »
Really Tews? Was hoping to be in the low 50s.

Bwaller: they aren't oily. But I've never seen oil fouled plugs so I'm not sure how they would look any different than rich fouled plugs.

Offline SOHC4 Cafe Racer Fan

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Re: Gentlemans Express Cb550
« Reply #91 on: July 26, 2016, 04:54:13 PM »
I have the 605 big bore kit like you. 650 cam, stage 2 head work from MReick and had 44hp on my best pull. Motogpwerks exhaust as well.

Is that the cruzinimage regular compression kit?
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Offline Retro Rocket

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Re: Gentlemans Express Cb550
« Reply #92 on: July 26, 2016, 04:56:21 PM »
Really Tews? Was hoping to be in the low 50s.

Bwaller: they aren't oily. But I've never seen oil fouled plugs so I'm not sure how they would look any different than rich fouled plugs.

When oil burns it leaves a greasy residue, oil fouled plugs may be the same color as rich fouled plugs but the oil fouled plugs will be greasy black, rich fouled plugs will be dryer and black. Ever felt the exhaust on a car or bike thats clearly blowing blue {oil} smoke..? It will be black and slightly greasy.... ;)
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Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #93 on: July 26, 2016, 05:58:20 PM »
Well that's got me thinking?!!. It really could be oil fouling, for the rings not being set. It is a little darker and not chalky black. Is that common with a super fresh motor? What's the cure?

Offline Retro Rocket

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Re: Gentlemans Express Cb550
« Reply #94 on: July 26, 2016, 06:10:20 PM »
If you're burning oil you'll be blowing some bluish smoke...
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Offline bwaller

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Re: Gentlemans Express Cb550
« Reply #95 on: July 26, 2016, 06:43:02 PM »
Tell Paul the engine is fresh and some slow pulls on the dyno is a good approach to seating rings.

Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #96 on: July 26, 2016, 09:05:11 PM »
Black smoke is what I'm seeing. Bike at most has 15 miles on her, so I'm sure that the rings haven't set yet. But then not being jetted correctly, I can't really put the miles on her to set them. Double edged sword type of thing. Good call on the dyno pulls Bwaller. Hopefully those slow pulls will give us enough info to jet properly.
It is the cruzinimage piston set cafe fan. No offense Tews but with all the work we did I'd be kinda bummed if I only saw 6hp over stock.

Offline Tews19

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Re: Gentlemans Express Cb550
« Reply #97 on: July 27, 2016, 07:13:33 AM »
Yes the cruzinimage 605 piston kit off eBay. I am going to get it dyno'd soon this season since the carbs are all syncd
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Offline calj737

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Re: Gentlemans Express Cb550
« Reply #98 on: July 27, 2016, 07:22:56 AM »
If carbs are off you will have 37 first pull, middle pull 44hp, and third pull 38hp...
This is probably very close on the numbers. A 650 cam, larger low compression pistons won't do much for you in the HP arena, and your carbs are stock, not "heavy breathers".

Never spend the money to make a vintage bike a "fire breather". Spend it because you enjoy it, love the final product, and disregard the fact that for 1/2 as much you could buy a brand new UJM that would put you on your butt through an intersection. Who cares, right? Its yours and you have built it. At the end of the day, HP is about bragging rights, and its paper, not reality. Can you really ride the difference?
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Offline Camrector

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Re: Gentlemans Express Cb550
« Reply #99 on: July 27, 2016, 07:26:22 AM »
Good point Cal. You are exactly right

Tews:I bet though that you'll see better numbers now with your carb sync.
Even with my carbs not jetted correctly now, this is the fastest cb550 I've ever been on. Dropped a fair amount of weight which is probably the main difference.
« Last Edit: July 27, 2016, 08:00:54 AM by Camrector »