Author Topic: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF  (Read 19443 times)

0 Members and 1 Guest are viewing this topic.

Offline tauruck

  • Hero Member
  • *****
  • Posts: 5126
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #15 on: January 27, 2014, 03:10:29 AM »
It's the nature of the beast. HD rear cylinders always run hotter.

Maybe they should make some barrels with longer fins. :-D :-D :-D

Might not be pleasing to the eye though.

Offline fordboy628

  • Hero Member
  • *****
  • Posts: 2342
  • GONE FISHIN' . . .
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #16 on: January 27, 2014, 07:52:30 AM »
I know, Briz.  What I am showing Patrick how to do is to cool it down a little without hurting performance.  Most of my experience is with the center cylinders on Jap triples, the inner cylinders on Jap fours, and the hotter running cylinders on other motors.  My figuring is the principles are the same.

Tonight I will look in my used plugs box and see if I can take a picture of the ring I am talking about.  It tells about the spark advance, at least on gasoline powered engines.  The rings should be the same distances down the center electrodes on both plugs if the spark leads are the same for both jugs.  A ring that is further down one electrode than the other indicates the timing is advanced in that cylinder.  That is something to check for and it is not uncommon.

The next thing to check is to put the pistons and cylinders back on and to check the deck heights on each cylinder at TDC.  A piston that projects up further than the other can cause problems.  This is also a good time to measure the bores and how far the pistons are from the decks at BDC.  The eroded head is reconstructed with modeling clay and all four heads are cc'ed, the head gaskets are measured and the static compression ratio is calculated for both cylinders with the old and new heads.  The measured compression ratio should not be higher for the back cylinder.

The measured ratios can be a real "eye opener" a lot of the time.

The last thing is to verify there are no air leaks in the plumbing, or constrictions, to the hot jug or other things that cause it to run leaner than the cooler one.  This does not apply here, but it is good to remember on two carb bikes with one carb in the back is the rear one can be sucking hotter air than the front one.  It is not unusual to have slightly different jetting on the front and rear carbs. 

At this stage any problems are corrected, and if needed, and I richen the mixture to the hot cyl and lower its compression until it cools down.  This is what I do, it seems to work, and I am no fancy engine tuner.  Tell me if I am wrong on anything or if there is a better way.

x2!   Your procedure is right on the money!

The generalized tried & true dyno tuner's methodology for repairing/band aiding a hot/weak cylinder:

1/    Determine which cylinder(s) is(are) the problem.
       a/    via s/plug check
       b/    via EGT
       c/    via fuel flow differences
       d/    via air flow differences
       e/    via ignition timing check, per each cylinder
       f/     via localized coolant temperature check  (mostly for water cooled engines)
       g/    etc, via data logging/other data accumulation
       h/    C/ratio double check for differences in: chamber cc's, piston deck heights, valve relief depth, crevice volume, etc.

2/    Equalize or repair any discrepancies found, if possible . . . . . .

3/    Compensate for any discrepancies in the weak/hot cylinder that can not be equalized or repaired.
       a/    richen fuel
       b/    retard ignition timing
       c/    lower coolant temperature                           (this can be trickey/impossible with air/oil cooled engines . . . .)
       d/    increase coolant volume                              (again, this can be trickey/impossible with air/oil cooled engines . . . .)
       e/    lower air/fuel temperature
       f/     lower compression ratio of weak/hot hole     (obviously, this is a last resort)

4/    Confirm your corrective action
       a/    via s/plug check
       b/    via dyno run data
       c/    via EGT
       d/    via other data accumulation
       e/    etc.

Yeah, I know it's a long and complicated list and process.    But it sure beats coating the inside of your exhaust system with aluminum, or driving over a con-rod/piston . . .

It's why they call it development engineering . . . . . .

Everyone and anyone feel free to add to this list or chime in on your experience/solution(s).
 :cheers:
Fordboy
Science, NOT Magic . . . .

I used to be a people person.  But people changed that relationship.

"There is nothing permanent except change."    Heraclitus

"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."     Albert Einstein

Offline thefrenchowl

  • Sr. Member
  • ****
  • Posts: 414
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #17 on: January 27, 2014, 08:59:39 AM »
Hi,

Thanks for the procedures, I'll read them thoroughly and see what I can implement on this vintage bike of mine...

Don't forget we landed the bike at Speed Week 2011, only ran it at idle before that, no tuning, no dyno... and we proceeded to do my rookie run at 107mph, only for me to hurt meself the next day and go back home with only the one run in a week...

At the moment, we' re trying to find a venue in GB to run the bike as is and get some miles and info in the bag... Pendine Sands in Wales will probably be on again in May or June, but think again if you thought Bonneville was bad on traction... Sand is probably 10 times worse... A aeroplane strip would be ideal really to gather data...

Bye for now, all my thanks, Patrick
Flat Head Forever

...What exactly are we trying to do here?...

Offline SaltPeter

  • Full Member
  • ***
  • Posts: 171
  • Can't you just be Serious for once in your Life!
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #18 on: January 27, 2014, 11:08:03 PM »
Hi Patrick

Even my 1993 Suzuki V Twin Liquid Cooled 250cc 2 Stroke came standard with different Jetting on each cylinder.

Pete :-D
The Mission is to go as fast as possible along on that old Road Less Traveled.

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #19 on: January 28, 2014, 01:07:51 AM »
There are land speed meets in GB on runways.  They occasionally write about them in magazines.  There is a really long one they used for the Concorde, as I recall.

Offline Briz

  • Full Member
  • ***
  • Posts: 160
    • Custom cycle developments
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #20 on: January 28, 2014, 08:39:13 AM »
Only one in regular use is Elvington. Used for sprint meetings. Not hugely long.
Sometimes they allow meetings at RAF Honington; mostly a Huyabusa-fest. But its an active airforce base and bureaucracy is onerous. Some years they cancel for 'operational' reasons.




Offline thefrenchowl

  • Sr. Member
  • ****
  • Posts: 414
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #21 on: January 28, 2014, 08:51:23 AM »
Yep, I tried to get into the Busa meets... They wanted me to go at the same rpm as they go on the noise meter... They test at 4500rpm from a 9.500+ max rpm ... 4500rpm is about 80 % of my rpm range...

When I pointed that I needed to test for noise at 1800 rpm or so to be on the same % as them, they never came back to me...

They think they're proper bikers but in fact they never went out of their way to help me tune me bike...

Make it what you want, but I'm not a beggar...

Next club???

Briz, the NSA use to have a vintage content, but they seem very sleepy these days...

They used to run Elvington as a weekend, 1/4 mile on the Saturday, the mile on Sunday... Some of the best parties I've been to were there on the Saturday nite in the mess... That's in the mid 1990s... Time flies...

Patrick
« Last Edit: January 28, 2014, 09:00:50 AM by thefrenchowl »
Flat Head Forever

...What exactly are we trying to do here?...

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #22 on: February 05, 2014, 01:11:09 AM »
There is a speed event at Montlhery near Paris in 2015.  According to this magazine article in the July 2013 issue of The Classic Motorcycle:  "Vincent Chamon and the team from Association Vintage Revival run a slick event so that riders and drivers get the maximum possible time on the banking."  See www.vintage-revival.fr for info and www.cameravitesse.com for pictures.  A lot of land speed records were set at Montlehery.  This event sure looks like a fun way to get some seat time on the old HD.

Offline thefrenchowl

  • Sr. Member
  • ****
  • Posts: 414
Re: Harley-Davidson 1954 900cc KHK improvements for Speed Week 2014, APS VBF
« Reply #23 on: February 05, 2014, 08:43:20 AM »
Yes, Wobblywalrus,

The Vintage Revival meet is probs the best meet in Europe, if like me, you don't think you need to have  old faded fatso stars overpaid to ride outa priced machinery at classic meets to steal you own ride time... It's low key and the machinery to be seen there is, well, out of this world... And both cars and bikes ;-)

Haven't been yet, but loads of my friends have and rave about it...

BUT, the Montlhery track oval is well damaged, no way you can go round the 2 miles and stay on the banking. A whole 1/2 circle is actually closed. The other 1/2 circle has 2 or 3 chicanes to avoid the worst of the pot holes (I mean pot holes you could sink a car in :-)...)



They would also want a front brake no doubts ;-)

I know I should test, but I'm not too worried about it. We know from last year where the bike wants to go, so it's just a matter of making it stronger and slipperier...

So, if we can test, it's just a bonus...

Patrick
« Last Edit: February 05, 2014, 11:01:25 AM by thefrenchowl »
Flat Head Forever

...What exactly are we trying to do here?...

Offline thefrenchowl

  • Sr. Member
  • ****
  • Posts: 414
Hi all,

Getting near!!!

The bike was finished yesterday, I wheeled it out of the garage for a few shots and the sun showed its face as well...

The new crate will arrive at work next week. Will get some help from Alan and his van to bring the bike there as well on Monday.

Airfreighters will collect it towards the end of next week...

As usual, last minute . com... Do not even intend to start it here, we'll see once on the Salt Flats.

See you all at Speed Week...





Bye for now, Patrick
Flat Head Forever

...What exactly are we trying to do here?...

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
It looks great.  Have a good time and enjoy the sun.

Offline tauruck

  • Hero Member
  • *****
  • Posts: 5126
Patrick, I added a little touch. :cheers:

Offline thefrenchowl

  • Sr. Member
  • ****
  • Posts: 414
Bike crated and gone last Friday... We're getting near...





Patrick
Flat Head Forever

...What exactly are we trying to do here?...