Landracing Forum Home
November 20, 2017, 12:05:28 PM *
Welcome, Guest. Please login or register.
Did you miss your activation email?

Login with username, password and session length
News:
BACK TO LANDRACING.COM HOMEPAGE
 
   Home   Help Search Calendar Login Register  


(Note: Donations are not tax deductible)







Live Audio Streaming and Archives of Past Events
Next Live Event: TBD
Pages: [1]   Go Down
  Print  
Author Topic: Little things and A/APS-PF-650 prep  (Read 2409 times)
0 Members and 1 Guest are viewing this topic.
JimL
Sr. Member
****
Offline Offline

Age: 71
Location: Sutherlin, Oregon
Posts: 739





Ignore
« on: May 05, 2013, 11:31:51 PM »

Soooo....today I learned another "little thing", and it got me thinking about all the dumb mistakes and strange goofs over the past four SpeedWeeks.  This first picture is a REALLY little thing, but it turns out to be the rest of the story from my last return run in 2012.  As I described last year, the qualifying run was limited by a combination of wet salt and fear.  The return run went much better, up to a point.  The bike has always had trouble pulling the big split between 4th and 5th, but the return run was strong (158 1/4 speed) and starting to get on the pipe in 5th.  About half way through the 3 mile, it just went flat and pretty much quit accelerating.

Fast forward to the present.  Last week I pulled the cam and replaced it.  Another little thing....I went the wrong way on the cam three years ago, in fact less lift and duration than stock....(please dont ask.) embarassed  That may have a little to do with the lack of power for the last three years with my 650 and 680 engines.  The new cam is much more appropriate, and I had to clay the piston valve pockets to confirm clearance.  With the rear cylinder head off, I was surprised to find no carbon.  Just a little gray smoke.  The front cylinder has a nice light brown film....just right.

I figured I'd have to take the carb apart (again) and see what gives.  Before I got to that, I mounted the carbs up, and was opening the throttle to check synch had stayed.  I was surprised to see the needle from the rear slide staying in the jet, with just the slide going up and down!  I only found the half of the clip shown in the pic....the rest must have gone out the tailpipe.  I suspect the needle was pulling up partially, and thats what made it so lean.

Another "little thing" I found while changing the cam.  My son told me he heard a knock at the line, waiting for my return run.  I thought it sounded ok.  He was right.  Before 2012 event I had the engine apart to install the destroke crank and get a fresh bore from Jellybean.  I goofed again.  I left both cam bolts loose, they backed out, and beat up the back side of the back case.

I could write a book of all the mistakes with this project, but I think I may never get to "the end".

The second pic is the new radiator mount, in stock type CX position, so I can run unstreamlined class.  The previous tank had a little slant to the front, and the radiator was behind the engine.  Talking to the officials, it could have been ruled streamlining, so I put a stock radiator (for this engine) right up front and vertical.

JimL


* clip.JPG (302.27 KB, 960x720 - viewed 186 times.)

* A rad mount.jpg (144.18 KB, 960x720 - viewed 292 times.)
« Last Edit: May 05, 2013, 11:40:03 PM by JimL » Logged
DND
Sr. Member
****
Offline Offline

Location: Granada Hills Ca.
Posts: 395





Ignore
« Reply #1 on: May 06, 2013, 10:06:40 AM »

Hi Jim

In 67'-68' i worked at a race engine shop and the boss made up a printed check off sheet ,that went along with each engine so you could tell that each part was installed right & tight too.

They really do help as it is hard to remember it all, one for the bike might be a good thing too.

Don
Logged
panic
Sr. Member
****
Offline Offline

Age: 72
Location: Lynbrook, New York
Posts: 755



WWW

Ignore
« Reply #2 on: May 06, 2013, 02:05:58 PM »

An interesting article in the New Yorker described a finding in which cardiac surgeons of international rank still left sponges and retractors inside patients - but (unlike mere mortals) refused to discuss using a check-list until their insurance carriers suggested a rate increase of $100,000 per year for their liability coverage.
Eventually, hospitals will discover that the soothing music played during critical surgeries increases the error rate.

Airlines already know this: all personal (non-official) conversation is officially verboten in the cockpit - good thing they hide this very well, or they'd be bankrupt long ago.

Multi-tasking does not exist.The smallest distraction is deducted from your focus. Letting something slip by is not a competence problem or an IQ problem, and no one is immune.
The person who did the assembly work should not do the final check - he can't see his own errors.

Obvious, you say?
Perhaps, but it took me 50 years to learn.
Logged
Stan Back
Hero Member
*****
Offline Offline

Location: San Berdoo
Posts: 4757





Ignore
« Reply #3 on: May 06, 2013, 04:44:55 PM »

Ewe shouldnt proofreed you're owne stuf; ether.
Logged

Member of the San Berdoo Roadsters California's most-exclusive roadster club.
Celebrating 65th anniversary of racing on the salt.
Koncretekid
Sr. Member
****
Offline Offline

Age: 70
Location: Yarmouth, Nova Scotia & Lafayette, Co.
Posts: 991





Ignore
« Reply #4 on: May 06, 2013, 09:53:43 PM »

Jim,
All those blunders and still, 158 mph on a 650 pushrod motor!!!!  I'm think about building a 600 motor for the BSA - - glad I only run at BUB.  Actually, the competition with you would be fun - old Brit design versus the "modern" Honda.
Tom
Logged

We get too soon oldt, and too late schmart!
Life's uncertain - eat dessert first!
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4442





Ignore
« Reply #5 on: May 06, 2013, 11:34:24 PM »

In my younger days I could do two things at once, like I was service manager and a mechanic.  No more.  Now I am lucky to one thing right at a time.  This helps.

Put a dab of fingernail polish on each bolt or screw that is torqued down tight.

Do one task at a time.

Keep notes.

Double check everything.

Don't drink beer during the final assembly. 
Logged
Old Scrambler
Sr. Member
****
Offline Offline

Age: 70
Location: Plymouth, WI
Posts: 629


Going Fast - Slowly




Ignore
« Reply #6 on: May 07, 2013, 06:45:55 PM »

The first test of the B-29 Aircraft crashed because the best test pilot forgot to change the flap setting.  The check-list for all flight-lines was then invented. 
Logged

2011 AMA Record - 250cc M-PG TRIUMPH Tiger Cub - 82.5 mph
2013 AMA Record - 250cc MPS-PG TRIUMPH Tiger Cub - 88.7 mph
2016 AMA Record - 750cc M-CG HONDA CB750 sohc - 130.7 mph
2016 AMA Record - 750cc MPS-CG HONDA CB750 sohc - 137.7 mph
Chasis Builder / Tuner: Dave Murre
JimL
Sr. Member
****
Offline Offline

Age: 71
Location: Sutherlin, Oregon
Posts: 739





Ignore
« Reply #7 on: May 07, 2013, 09:03:32 PM »

More "little thing" problems.  The new 41mm carbs would not idle down.  Fortunately, just at the moment I was about to lose it, Don J (Salt27) appeared.  This was serendipity, because it meant I had to calm down, be rational, and pretend I knew what I was doing. tongue

While we visitied, I compared the new carbs to last years 39s and realized the slides were not going down as far in the bore.  Hmmmmm.  Both sets of carbs are ProSeries which have special machining by Mikuni.  I took the slides out of last years carbs and found they are identical, except....the bottom stops are machined off to the tune of 0.7mm.  With the old slides, in the new carbs, it now idles down.  The issue is caused by the boring operation in the throat, which lowers the floor of the bore.  Somebody dropped the ball and didnt finish the job on these 41s.

Line item on checklist:  Order race team espionage agent to obtain engineering drawings and notes for all supplier parts, as soon as agent "Bonnie, the cat" grows opposable thumbs.

 I keep telling myself...."its just a simple pushrod twin."  Sure is a good thing we all have a sense of humor. rolleyes

Thanks everyone, for the good perspective.
JimL
Logged
Cereal KLR
Full Member
***
Offline Offline

Location: San Mateo, California
Posts: 136





Ignore
« Reply #8 on: May 07, 2013, 09:08:19 PM »

I do the check off list and the telltale paint on torqued fasteners, and thought I was pretty cool with my sure fire methods. Got to Bonneville and the little woman calls and say "Your helmet and leathers are here on the kitchen table"...
Logged

I thought I would die young, but now its too late.
salt27
Hero Member
*****
Offline Offline

Age: 60
Location: S.W. Orygun
Posts: 1241





Ignore
« Reply #9 on: May 07, 2013, 10:40:30 PM »

More "little thing" problems.  The new 41mm carbs would not idle down.  Fortunately, just at the moment I was about to lose it, Don J (Salt27) appeared.  This was serendipity, because it meant I had to calm down, be rational, and pretend I knew what I was doing. tongue
JimL

Jim,
 Looking at your impressive bike just confirmed something I've suspected for sometime, I'm a hillbilly. grin

Thanks for all the info, Don
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!


Google visited last this page June 02, 2017, 09:22:50 AM