Topic: 550 with Cruzinimage 605 kit and Mrieck Head work with Dyno print out& VIDEO

[Tews19]

I finished my 550/605 build kinda. It's riding season right now so the cosmetic things will be taken care of later.

As on now I have the cylinder bored to 605, 650 cam, MRiecks stage 2 head work, Dyna ignition and coils, MotoGPWERKS exhaust. I did a Dyno run today and the HP was at 44 on the best pull. Not impressive but at least I am above 35 at the wheel which I wanted. I still need to figure out the carbs but I am hoping some may be able to help me read/decipher this dyne run. Here is a copy of the print out. I will be going back Tuesday to rerun after I resync  the carbs.

[bwaller]

What carbs, filters?

[Tews19]

Ooops sorry I should have mentioned that. Stock 069a carbs, mains 105 slows 38, 1.75 turns out. Stock filter as well.

[MCRider]

I finished my 550/605 build kinda. It's riding season right now so the cosmetic things will be taken care of later.

As on now I have the cylinder bored to 605, 650 cam, MRiecks stage 2 head work, Dyna ignition and coils, MotoGPWERKS exhaust. I did a Dyno run today and the HP was at 44 on the best pull. Not impressive but at least I am above 35 at the wheel which I wanted. I still need to figure out the carbs but I am hoping some may be able to help me read/decipher this dyne run. Here is a copy of the print out. I will be going back Tuesday to rerun after I resent the carbs.

Not too shabby. A Hawk GT650 Dynos about there. If you've got some carb work to do, youll get better.

[Jerry Rxman Griffin aka MuthaF'er]

Did you get an air/fuel graph?

[Tews19]

Did you get an air/fuel graph?

I am going back Tuesday to do that. It was a mobile Dyno truck. It was the grand opening for a Victory store and he was there. He said for 20 bucks he can help me tune it. Sounds pretty fair to me..... The numbers aren't as high as one may think but the bike is running very well.

The dyno guy did say to do a proper check with the sniffer thing he would technically drill a hole in each pipe as close as he could to the exhaust leaving the engine. Then measure each pipe individually. But since it is not  his bike he will put the sniffer as far as he can go through the exhaust.

Does this sound correct?

[scottly]

Run 3 goes off the top of the chart at about 68 MPH; the dyno operator has apparently scaled the chart incorrectly. I suspect your max HP to be 4 or more higher than the print shows, based on the angle of the curve before it goes out of sight. Have him give you a print of run 3 alone, as runs 1 & 2 were apparently warm-up runs at less than full throttle.
There is no need to drill holes in the exhaust pipes for the sniffer with your 4-1 exhaust; the 1/4" copper tube can be snaked into each pipe, but tuning each cylinder individually is generally not required.   

[turboguzzi]

a lot of the hp gains from a big bore kit will depend on what kind of compression ratio and squish you built into the motor. any idea? if you dont know, not so good.....

not a big fan of dyna ignitions, have you timed it with a strobe? if not, would advance it until you start getting some ping and then back off just a bit for best power.

last, one dyno run is nice to get an idea, but until you start going up and down with jets you will not have much way of knowing how spot on you are with mixture. A/F ratio on slide carbs is only some relative help, from my experience best to use WOT power as an indicator for the main jet size.

[calj737]

There is no need to drill holes in the exhaust pipes for the sniffer with your 4-1 exhaust; the 1/4" copper tube can be snaked into each pipe, but tuning each cylinder individually is generally not required.

This will be very difficult to do unless the tailpipe section is removed due to the baffle. Removing the tailpipe to analyze each cylinder will then distort the HP as back pressure is removed. A single analysis of the exiting gas is about all you'll get here- and that should be more than sufficient for a daily driver, street bike.

[PeWe]

Have you read this thread? CB550 with almost 70whp. I guess it has higher compression that add some.
Your bike should be in the +60 I guess...
http://forums.sohc4.net/index.php?topic=40414.0

[Tews19]

There is no need to drill holes in the exhaust pipes for the sniffer with your 4-1 exhaust; the 1/4" copper tube can be snaked into each pipe, but tuning each cylinder individually is generally not required.

This will be very difficult to do unless the tailpipe section is removed due to the baffle. Removing the tailpipe to analyze each cylinder will then distort the HP as back pressure is removed. A single analysis of the exiting gas is about all you'll get here- and that should be more than sufficient for a daily driver, street bike.

Your last sentence is exactly how he stated it. It is more than sufficient for a daily driver. The gentleman was highlighting specifics when it comes to his bikes and his process.

Pewe I will check out the thread, thanks for linking it.


My next question is when syncing the carbs I have read multiple times on here it doesn't matter where on the dials the needles are. As long as all 4 needles are in the relative area of one. But in the manual it states to have them at a certain hG? Is this correct?

Lastly how is one able to learn how to do a Compression ratio check? Any links I am able to read up on to learn?

Here is the dyno run...Watch "Honda CB550 dyno" on YouTube

[calj737]

Your last sentence is exactly how he stated it. It is more than sufficient for a daily driver. The gentleman was highlighting specifics when it comes to his bikes and his process.

Yeah, thanks I read that. The point I was making is that you can't snake the analyzer on a MGP system due to the baffle. I wasn't disagreeing with him either, merely expounding upon why the sample of your total system is more than sufficient (as he said too).

[Tews19]

Sweet! So maybe I get ballsy and remove baffle? Or leave It in due to loss of back pressure while running a dyno will alter the actual bike setting?

[calj737]

See my prior post-

[Tews19]

See my prior post-

Distort!!! I got ya! I think you are starting to get to know me a lil t0o much. You know I skim at times and not fully comprehend what was stated. I have the manual and I am going to attempt to sync per the manual specs. It's raining so nothing better to do with the bike right now.

[calj737]

Who among us doesn't miss something every now and again? 

[Tews19]

a lot of the hp gains from a big bore kit will depend on what kind of compression ratio and squish you built into the motor. any idea? if you dont know, not so good.....

not a big fan of dyna ignitions, have you timed it with a strobe? if not, would advance it until you start getting some ping and then back off just a bit for best power.

last, one dyno run is nice to get an idea, but until you start going up and down with jets you will not have much way of knowing how spot on you are with mixture. A/F ratio on slide carbs is only some relative help, from my experience best to use WOT power as an indicator for the main jet size.

Turbo I have timed it. It's spot on and yes I used a timing light.

[bwaller]

Forget trying to sniff each cylinder, takes way too much time for the small gain, plus it gets too complicated.

It seems you have a good handle on the hp figure too. It's only a number, don't dwell on that. I find I can easily feel a four hp increase. You're way over that and you'll be happy with the increase.

Synching carbs- even the dials. It'll be obvious when you're close. It takes some fiddling to button it up after as settings can change. Be patient and use a large fan in front of the engine to move some air over it.

I'm not going to re-read so some things have already been mentioned. Stock ign settings will likely make it happy. If you want to try a couple degrees either side of stock, do that first before carburetion. Try to mark your existing spot so you can easily get it back there then approx. 1/16" rotation clockwise of the plate retards timing by +-2 degrees or vise versa. If you are adventurous and move it around to no avail then reset to the original mark for carb tuning. You can re-test with a strobe later. Flat top pistons and small 500 chambers don't need much ignition lead, but with 1:10CR or so stock settings may be best.

 A dyno will help find the mainjet with WOT pulls. This is where you should focus. With a sniffer get that right and be happy. For the street though you may need to do some work on your own as far as needle settings & pilot selection. Just for giggles try raising the needle by 1 clip. I have found even with increased vacuum from a fresh top end I always need a larger pilot jet for that "off idle" bog we get pulling away from a stop. Try the air screws first but any more than 1 turn from stock settings will require a jet change, usually larger for me. I like to use tapered jet reamers, others have jet drills, but if you can find the right size pilot so much the better.

Calculating CR....Swept volume +combustion chamber volume, divided by that volume.

Swept volume =finished cylinder bore x bore x stroke (50.6) x 0.7854 divided by 1000 =cc's

Chamber volume includes
1) chamber (500/550 is 13cc's) plus 2) head gasket (calculate this the same as cylinder swept vol.) plus  3) piston net dome (may be 0 with yours) plus 4) piston above or below deck value (unless it's even with the deck) plus 5) piston compression shoulder to top of 1st ring. This is a small  value but for accuracy...

For example 605 kit is 61.5mm? Lets figure you asked for 0.001" piston clearance (0.025mm) so swept volume is 150.434cc

chamber volume is 13cc
head gasket, lets say stock thickness with a 62mm bore?? for 3.2cc
piston dome, lets say "0" for arguments sake.
let's also say 0.010" below deck....just guessing here. 0.74cc
comp shoulder to top ring (usually 3mm??) another guess at 0.295cc    for a total volume of 17.235cc

150.434 + 17.235 divided by 17.235 = CR 9.7

You can plug in your exact figures if you have them.

Good luck!

[Tews19]

Thanks for the great write up Brent. I am curious though in regard to "feeling a 4 hp gain, and you are over that" comment. What do you mean I am over 4 hp gain? I wonder what is the stock HP on a 550 at the wheel. I know the manual says 50 at the crank so I am thinking I should be over 50 at the crank?

[calj737]

You are over 50 at the crank, Tews if you're getting 44 at the rear. I've seen other report essentially 35-38 stock rear wheel on the 550.

[bwaller]

Cal's spot on. There was a guy here years back that planned an overbore on an otherwise good running stocker. He dyno'd the bike before he tore it apart and it was 36 RWHP.

[SOHC4 Cafe Racer Fan]

Have you read this thread? CB550 with almost 70whp. I guess it has higher compression that add some.
Your bike should be in the +60 I guess...
http://forums.sohc4.net/index.php?topic=40414.0

Paulages build is not walk in the park.  He was mating a 650 big bore top end to a 550 bottom.  The big bore was to the point of where he had to use 750 sleeves and overlap them into the cylinder -- much finesse required -- plus other machining to adapt the 650 top end. 

[Retro Rocket]

Not trying to be to negative here but, if you were interested in getting good HP improvements, why use cheap, stock type compression pistons, especially with one of Mike's heads....? Put some decent pistons in it, tune it well and watch it go from good to great...

[Tews19]

RR I got these pistons when were relatively new. I figured for the price and lack of knowledge on them I would use and share the outcome with them. That's all. I didn't take your comment as negative either.  Plus this bike was never planned to be a daily rider.

[Retro Rocket]

RR I got these pistons when were relatively new. I figured for the price and lack of knowledge on them I would use and share the outcome with them. That's all. I didn't take your comment as negative either.  Plus this bike was never planned to be a daily rider.

Yes, I wasn't trying to be negative, I understand you using the dyno for tuning, its a great help, actually, its the best way full stop.
Still, you will notice even 4 or 5 hp over a stocker, thats a good improvement, if you want more, stick some 10 to 1 pistons in there and feel what that head is capable of and enjoy some more power....   Downside, you may want bigger carbs....