Donate!
Welcome, Guest. Please Login or Register :: View Members
Pages: 1 2 3 4 
Send Topic Print
Big Bore Engine - Part 6 - Test & Tune (Read 363 times)
DragBikeMike
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 4071
Honolulu
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #30 - 09/22/20 at 00:55:20
 
I modified the ignition pickup so I could dial in an additional 2°of advance.  Maybe I can bring the temperatures down a bit more.
Back to top
 

Advancing_Timing_1_2.JPG

Knowledge is power.
  IP Logged
DragBikeMike
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 4071
Honolulu
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #31 - 09/22/20 at 00:56:47
 
When it was all back together, I let it sit for several days to allow the sealant time to set up, then the engine went back in the frame.  By this time, I’m getting pretty good at the R&R.

Now it’s time for some advice.  I’m getting old, slowin down, things get a bit foggy sometimes.  If you are in the same boat, take heed.  I poured the first quart of oil down its throat and was twistin the cap off the second jug when I got an itch to glance at the bullseye.  It was maxed out.  Did I pour in two quarts????   No way.  Why is it maxed out with only one-quart of oil?  Is it level?  Ummmmmmm!  Did I remove the cleanliness plugs?

I like to plug up the holes in the crankcase with paper towels to keep little parts from getting lost in the engine.  It’s easy for an old geezer wandering around in a fog to forget something like that.  I guess I have to come up with a tag-out system.  This could have been disastrous.  From now on, I’m gonna place a zip tie through one of the cover bolt-holes whenever I use cleanliness plugs.  Hopefully, that will remind me to check before I install the cover.  How did I miss this???
Back to top
 

Cleanliness_Plug_Problem2.jpg

Knowledge is power.
  IP Logged
DragBikeMike
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 4071
Honolulu
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #32 - 09/22/20 at 00:58:19
 
A quick compression check showed it now pumped 210 psi.  That extra 350 miles of break-in must have done the trick.

It ran great.  Started right up and everything seemed the same, including the oil leak.  Ya gotta be kiddin.  The joint looked solid.  You could see a fine bead of sealant squeezed out completely around the circumference.  The fasteners along the right side of the head were squared away and plenty tight.  It met the flatness spec.  But the leak was still there.
 
I put another 150 miles on it so I could evaluate the advanced timing.  The temperatures remained about the same and it ran just a tad slower.  Looks like the factory setting (30°) is the way to go.

Before I tore the engine out of the frame again, I did another air test.  No bubbles.  I spent a good long time pumping it up and soaping everything down.  I even evacuated all the oil out of the lubrication system to make sure air was filling all the passages.  Still no bubbles.  I can see this is going to be a tough problem.  I’m leaning toward using the stock multi-layer steel (MLS) gasket.

The cylinder is really beat up.  It’s a junker that I bought on eBay.  It’s got a bunch of bent fins and one is broken.  There’s also evidence of some separation between the sleeve and the aluminum cylinder.  I thought it was the perfect candidate for learning how to bore a cylinder.  I might try and round up a dye penetrant kit and see if there is a hairline crack.  Not sure yet.
Back to top
 
 

Knowledge is power.
  IP Logged
DragBikeMike
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 4071
Honolulu
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #33 - 09/22/20 at 00:58:53
 
This is a shot of my sophisticated air test equipment.  How could any leak hide from this test gear?
Back to top
 

Air_Test_Rig_1_2.JPG

Knowledge is power.
  IP Logged
DragBikeMike
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 4071
Honolulu
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #34 - 09/22/20 at 01:01:13
 
The 94mm is back in the motorcycle.  I have some other projects I want to play with.  In the meantime, I will keep plugging away at the 97mm.  It runs too darned good to give up on it.  I will solve the leak.
 
What have I learned so far?

The cam, head, carb, exhaust-header combination is totally sweet.  The components work great together.  The beast is blazin fast with a broad linear power band.
 
The oversize 1.79” header pipe is not too large.  It works good on the 94mm and great on the 97mm.  Contrary to popular belief, it doesn’t kill torque.

The Stage III head works great.  The Honda 34mm intake valves don’t present geometry problems.  The SuperTech Subaru valve springs work perfect and are a bargain.  The Kibblewhite spring retainers and cotters also fit & work perfectly, and they didn’t crack.  The supersized exhaust port doesn’t kill torque.  The engine signs-off a bit earlier so I might revisit the intake port, maybe see if I can squeeze a bit more flow out of it.

The Wiseco 97mm runs significantly smoother than the 94mm.  The additional 41 grams of weight brings it much closer to the stock piston weight and keep vibration levels close to stock.

The forged 97mm runs quiet, it’s not rattling around in the cylinder.  The dreaded forged piston slap is not a problem.

The 10:1 compression ratio and 210 psi cranking pressure do not cause detonation problems.  It runs great on 92 octane pump gas.

The hobby lathe bore job is within the capability of the average bear.  The rings bedded in nicely and it doesn’t have blow-by problems.  It doesn’t build up pressure in the crankcase at WOT.
 
The ignition timing is critical to limiting oil and cylinder head temperatures.  Retarding the timing just 2° makes a big difference.

The Mac exhaust system is good for some more power.  Its too loud, but there is a measurable increase in performance.
Back to top
 
 

Knowledge is power.
  IP Logged
DragBikeMike
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 4071
Honolulu
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #35 - 09/22/20 at 01:02:37
 
I hope you find this report informative.  So far, it has been a fun project and I have learned a lot.  As always, I invite your comments and questions.  If any of you have CHT data to share, please post it.  Oh yea, be sure to remove those rags before you close up your engines.  Lips Sealed

Knowledge is power.

Mike
Back to top
 
 

Knowledge is power.
  IP Logged
zipidachimp
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 1380
surrey, b.c.
Gender: male
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #36 - 09/22/20 at 01:37:21
 
Mike, you are a bloody inspiration! Who needs more than 1 cylinder ? no one !
cheers! Cool
Back to top
 
 
  IP Logged
LANCER
Serious Thumper
Alliance Member
*****
Offline

Savage Beast
Performance Parts

Posts: 10565
Oklahoma
Gender: male
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #37 - 09/22/20 at 08:39:01
 
Very informative as always Mike.
Thanks for all your efforts.
Back to top
 
 
  IP Logged
justin_o_guy2
Serious Thumper
*****
Offline

What happened?

Posts: 55279
East Texas, 1/2 dallas/la.
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #38 - 09/22/20 at 09:27:33
 
Information like this, contacts with people,, folks.. this place is a trasure trove,, and I worry about it just going away. I dont know how to set up contacts or find a way to archive the How To stuff,, but I hafta admit, after seeing a forum I really enjoyed go away, and I lost touch with everyone,, and , well,, Its a bummer. I dont wanna repeat performance..

But I DO wanna know whats so tricky about a copper head gasket?
Why would the OIl be the problem?

Compression is a lot stronger pulse..
Back to top
 
 

The people never give up their liberties but under some delusion.- Edmund Burke.
  IP Logged
Dennisgb
Full Member
***
Offline

SuzukiSavage.com
Rocks!

Posts: 176
Maplewood MN
Gender: male
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #39 - 09/22/20 at 09:59:01
 
Fun read and awesome results.

Can you skim the surfaces to get rid of that .003”?

I don’t use copper gaskets anymore. Old school solid copper where you could anneal and reuse were okay but the laminated ones suck.
Back to top
 
 
  IP Logged
Ruttly
Serious Thumper
*****
Online

Thumpers Rule

Posts: 4959
Manteca , CA
Gender: male
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #40 - 09/22/20 at 11:30:49
 
DBM , What do you think ? Does your butt think you have broken thru the  
40 H/P mark ? Or not.
Back to top
 
 

The Topic Terminator
  IP Logged
Armen
Serious Thumper
*****
Offline

Half-Witted
Wrench-Jockey from
Jersey

Posts: 1430

Re: Big Bore Engine - Part 6 - Test & Tune
Reply #41 - 09/22/20 at 17:27:54
 
As always, awesome!
Thanks for sharing!
Moving these days. Just packed the box with the 97mm top end. Maybe this winter at the new digs.
I have a slightly different break in ritual than you, but yours seems to work well.
Keep 'em coming!
thanks,
-Armen
Back to top
 
 

In theory, theory and reality are the same. In reality, they aren't...
  IP Logged
DragBikeMike
Serious Thumper
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 4071
Honolulu
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #42 - 09/23/20 at 00:00:54
 
Thanks for the kind words.  I really enjoy doing these reports.

JOG, your comment regarding combustion pressure vs oil is excellent.  It is a mystery to me.  The thing seems to restrain the combustion pressure reasonably well, but the oil slips through the joint like greased lightening.  Crazy. The combustion pressure is through the roof and the oil pressure barely makes 6 psi.  There are some visual indications that look like there might be combustion leaks, but when it's running there's no evidence of combustion leakage.  Usually you can hear a combustion leak.  You can see from the pictures that the oil is everywhere in the joint.  It's nuts.  Maybe the iron cylinder liner seals better than the adjacent aluminum material.  I just don't know.  In a few days I will get up enough motivation to pop the head off and start working on it again. Right now, I'm taking a break from it.  Sometimes it helps to step back for a while.

Dennis, the copper gasket I'm using is a solid copper gasket.  I've never seen a multi layer copper gasket.  I haven't annealed the head gasket yet.  I used a new copper gasket each time I assembled it.

Ruttly, of course I broke the 40 HP mark.  The 94mm tight quench (TQ) engine dynoed at 41 HP.  This 97mm is significantly faster (stopwatch, not butt dyno) than the TQ.  It has to be making well over 41 HP.
Back to top
 
 

Knowledge is power.
  IP Logged
justin_o_guy2
Serious Thumper
*****
Offline

What happened?

Posts: 55279
East Texas, 1/2 dallas/la.
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #43 - 09/23/20 at 10:37:37
 
ennis, the copper gasket I'm using is a solid copper gasket.  I've never seen a multi layer copper gasket.  I haven't annealed the head gasket yet.  I used a new copper gasket each time I assembled it.

You gonna anneal it first?

Oven?

What about a copper washer at the oil passages,,
Or maybe a circular wrinkle, induced with some appropriate diameter piece of tubing?
I like the wrinkle idea better,, if you have room, one from each side, like ripples on a pond.
If I was gonna do that I dont think Id anneal it.

Ya now,, a wrinkle slightly outside the hole and a punch shoulder to press the hole the other way might get it,,

Could ya anneal Just the part that the liner squishes?

Naaah.. probaly heatin that would induce warping,, Hell I dont know,, Im not your level of mechanic, at all..

You can play with the one that comes out and see how it acts with heat applied,
Or maybe steal some of it to use as a washer, if that looks plausible,,
Which, it doesnt really,, an area twice as thick wouldnt come down flat,,
Im kinda curious about the wrinkle thing,,
Back to top
 
 

The people never give up their liberties but under some delusion.- Edmund Burke.
  IP Logged
Dave
YaBB Moderator
ModSquad
*****
Offline

SuzukiSavage.com
Rocks!

Posts: 17732
Camp Springs, Kentucky
Gender: male
Re: Big Bore Engine - Part 6 - Test & Tune
Reply #44 - 09/23/20 at 17:48:33
 
Great project and report DBM......fun stuff for us gearheads!

Like Jog, I wonder if a raised rib around the oil cavity would help get it sealed?  Suzuki has the rib in their head gasket - and they also have the oil migration issue a bit.  The oil doesn't seem to come out to the exterior - but it does migrate around to the studs at the intake and exhaust ports, and sometimes folks need to seal those points to keep the oil from weeping out.

I also wonder if you shouldn't try to improve the flatness - I am not sure if the Suzuki standards that are applicable to the stock multi layer and coated steel head gasket are applicable to a copper gasket.  I would sure be tempted to use the sandpaper and glass method of making a flat surface on the next try....and using a really soft copper gasket (new or annealed if necessary).

I have my cylinder head sensor on the left rear cylinder stud.  I chose that location as it is not at the exhaust port and isn't picking up heat from the stud that is exposed to the hot exhaust gasses.  On normal 2,500 - 3,500 rpm back road cruising on 80 degree days the temps are around 240 degrees.  If I get on the freeway and stay up at 70mph @ 4,000 rpm the temperature goes up about 20 degrees to 260.  On days where the temperatures are in the 90's I can see 280 on the freeway.  The hottest I have ever seen occurred while stuck in traffic on Main Street in Gatlinburg on a 90 degree day......the temperature got to 300.

Back to top
 
 

Someday I will be old......But not today!

  IP Logged
Pages: 1 2 3 4 
Send Topic Print


« Home

 
« Home
SuzukiSavage.com
03/28/24 at 10:10:16



General CategoryRubber Side Down! › Big Bore Engine - Part 6 - Test & Tune


SuzukiSavage.com » Powered by YaBB 2.2!
YaBB © 2000-2007. All Rights Reserved.