Landracing Forum Home
November 24, 2017, 04:20:38 AM *
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 ... 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 [168] 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197   Go Down
  Print  
Author Topic: Team Go Dog, Go! Modified Partial Streamliners  (Read 520979 times)
0 Members and 1 Guest are viewing this topic.
Interested Observer
Sr. Member
****
Offline Offline

Posts: 330




Ignore
« Reply #2505 on: August 06, 2016, 12:23:20 PM »

Wobbly,
Thanks to Woody’s further info and the graph he presented, I think you can see that the program is rather powerful and useful for doing what you are setting out to do.  Eventhough the $500 is a chunk of money, it is considerably less than I had anticipated and much less than earlier, less well developed versions from Optimum software.  If I were in your shoes I would spend the money and save myself a lot of time and random misguided half-hearted partial efforts to synthesize a viable engine.  It will involve a certain learning curve and require a level of patience and attention to various details, but at least it deals with the whole enchilada, from the inlet horns to the end of the exhaust.  And it will give you a better understanding of what all is going on in the engine.  I would agree with Woody’s advice to download and digest the user manual and take a look at the following video clip that shows an example of how it works.

http://www.worlddragracing.com/downloads/UsingDynomation5_1.html
Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2506 on: August 07, 2016, 12:48:35 AM »

The records in the 1000cc classes are fast and getting faster.  It is a very competitive dogfight and I need to get lots of power in a hurry.  This rocket science type computer modeling is my only alternative and I will take your advice.

Old Burt Munro went faster than I will ever go without any of this fancy stuff.   
Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2507 on: August 07, 2016, 11:15:36 AM »

The crankshaft in the bike has 360 degree crank pins.  It also has 40,000 + miles of street use, over 260 dyno pulls, and 9 years of land speed racing.  There is an almost new 270 degree crank in the bone pile with balancers.  Can the program we are discussing work with the interactions between two cylinders with uneven firing order?  The enhance scavenging from connecting the two exhausts together on the 360 motor helps me a lot.  The math is simple in that application.  The headers are the same and correct length to make it work.  I suspect that headers of different lengths will be needed with the 270 crank and I do not know how to figure this out. 

The 270 crank gives better traction and that is what they use on the flat track bikes.  Heck, if new cams will be ground it is a good time to do the crank swap.
Logged
Old Scrambler
Sr. Member
****
Offline Offline

Age: 70
Location: Plymouth, WI
Posts: 629


Going Fast - Slowly




Ignore
« Reply #2508 on: August 07, 2016, 02:16:10 PM »

Bo...........Lots of data on H-D 883 and XR motors............as well as Yamaha XS650 twins. The firing is at 270 and 360..............the crank is a 180..........Just like most of the Honda twins from '59 forward including current Shadow models.
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
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2509 on: August 07, 2016, 06:51:41 PM »

The 2001 through 2014 Bonnevilles, T-100's, and Thruxtons have crank pins at 360 degree spacing, and the Americas, Speedmasters, and Scramblers have 270 degree cranks with the crank journals 90 degrees apart.  The 2015 -on T-120 Bonnevilles, Thruxtons, and Speed Twins, etc have 270 degree cranks.   
Logged
bones
Full Member
***
Offline Offline

Age: 61
Location: sydney Australia
Posts: 117




Ignore
« Reply #2510 on: August 08, 2016, 02:17:48 AM »

Hi Wobbly
  How much HP does the computer say you can get with EVERYTHING  optimised?
  Will you get 10-15 hp? Which is maybe 5mph.
 Could you be better off developing the bodywork to get the increase in speed?
I know fiberglass is a bit@h to do,but I think aero is a cheaper and better way for speed when an engine is near its peak.

   cheers    Bones
Logged
Interested Observer
Sr. Member
****
Offline Offline

Posts: 330




Ignore
« Reply #2511 on: August 08, 2016, 07:42:25 AM »

Wobbly,
The following is a reply from Dynomation--

Dynomation will model multiple cylinder engines (1 to 16 cylinders). It will model collector exhaust systems. But Dynomation does not specifically model induction that joins two cylinders on the intake side. That is, if the intake valves from two cylinders are fed by a single port, this is not modeled. However, it makes little effect, UNLESS, those two joined cylinders draw charge during at the same time or have overlapping intake periods (like some early Mini engines). That does affect performance and is not modeled by Dynomation.

 

Thanks.

 

Larry Atherton

Motion Software, Inc.


Why do you want to change cranks?  Inspect the 360 for wear and cracks and put it back if OK.  It is also conceiveable to run individual pipes on a 270 if need be.

Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2512 on: August 09, 2016, 12:03:01 AM »

Thanks for the advice.  I downloaded the users manual and they have some info about this.  The 270 cranks have a longer and shorter  intervals between power pulses as compared to the 360 crank.  The tire can dig in and get better grip during the longer pulses.  The flat track Triumphs all use 270 degree cranks for this reason. 

My downfall this year was trying to do too much and when I had problems I had no time and money to rectify them.  It is best that I keep the 360 crank in the bike and concentrate on cams, intake, and exhaust, only.

The bike is going into the wind tunnel after I retire and I have more time to work on it.  Chassis work does not cost much and takes lots of effort so it is a good task for that time in life. 

This is Curly, the retimed exhaust cam I used as an intake cam.  It has exactly the timing I want and it satisfies piston demand.  The intake valve closes 29 degrees earlier at .050 than with Moe and this give a much higher dynamic compression.  Also, unlike Moe, it uses the standard size lifter buckets.  The bike ran real good with this cam.  Unfortunately, it ate the tappet buckets and I cannot use it.   


* 2016 Build 286.JPG (425.45 KB, 1440x1080 - viewed 50 times.)
Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2513 on: August 09, 2016, 11:49:36 PM »

This build diary shows basic tasks.  This is measuring figuring valve motion and cam timing.  The cam cards are often not accurate and various lift profiles can give valve motion properties that are not described on the cam card.  This is the intake cam "Larry."  It has been in use for seven or eight years.

The first step is to knock out the plugs in the cam ends.  It is important to replace these.  They are vital to maintain oil pressure on the cam journals.  Dorman plugs #555-007 and #555-092 work just great.


* 2016 Build 287.JPG (207.49 KB, 1024x768 - viewed 47 times.)

* 2016 Build 288.JPG (285.88 KB, 1013x768 - viewed 47 times.)
Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2514 on: August 09, 2016, 11:56:40 PM »

Sometimes a part needs to be washed and it is too much trouble to get out the pan, brush, solvent, etc.  The cam is put in a plastic bag with a little solvent.  The bag is closed and it is swirled around and shook up.  Then the bag is opened and the clean cam is removed.  This is a trick I learned at the track years ago.

The little triangular badge that says "Made in England" was removed and a hole was drilled to turn the crank with an allen wrench.  A cover was made to block it off when the engine is used.


* 2016 Build 289.JPG (230.88 KB, 1024x768 - viewed 49 times.)

* 2016 Build 290.JPG (222.75 KB, 1024x768 - viewed 45 times.)
Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2515 on: August 10, 2016, 12:01:15 AM »

This is another cover that is made to show TDC.  A scribe mark is exactly in the middle of the view down the hole when the pistons are at TDC.  The tool to hold the degree wheel is shown.  This is a double overhead cam engine.  A "double knocker" in British slang.


* 2016 Build 292.JPG (228.94 KB, 1024x765 - viewed 50 times.)
Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2516 on: August 10, 2016, 12:22:42 AM »

The degree wheel is installed.  It is marked in crank degrees.  Valve motion data is wanted at 10 crank degree intervals.  The crank turns twice for every cam revolution.  Valve motion data is recorded at every 5 degrees of cam rotation to get 10 degree readings in crank degrees.

The degree wheel is moved so it reads TDC when the pistons are at TDC.  Now, the crank is rotated until the valve is 0.001 lower than  full lift.  This is an indicated 44 degrees ATDC.  Then, the crank is rotated through full lift and stopped when the valve is .001 lower than full lift.  This is at indicated 53 degrees ATDC.  Full lift is calculated as (44 + 53) / 2 = 48.5 degrees ATDC indicated or 97 degrees ATDC actual.  This is more accurate than trying to find full lift directly.  There are several degrees of crank rotation when the valve appears to be at full lift.

Cam base circles are sometimes not round or concentric with the cam centerline.  A habit I have is to always check and set valve clearance on the base circle directly opposite of the cam lobe tip.  This is at 48.5 degrees ABDC indicated.  The cam is rotated to this and the indicator is "zeroed." 

There is no clearance between the cam base circle and the bucket during any of this measuring.  The cam is in contact with the bucket during all 360 degrees of cam rotation.  The importance of this will become apparent later. 

   


* 2016 Build 293.JPG (202.47 KB, 800x600 - viewed 41 times.)

* 2016 Build 294.JPG (219.71 KB, 1024x768 - viewed 44 times.)
Logged
wobblywalrus
Hero Member
*****
Offline Offline

Age: 64
Location: backwoods Oregon
Posts: 4449





Ignore
« Reply #2517 on: August 10, 2016, 12:33:11 AM »

The cam is rotated five degrees at a time and the valve movement is recorded.  It is rotated through a full 360 degrees and the measurements are compared.  The lift was "0.000" at 48.5 degrees ABDC when the indicator was zeroed and lift is "0.000" at the same position after the measuring is done.  This is called a closure check and it shows that the dial indicator was not knocked out of position during the measuring.  This is one reason to make sure there is no clearance between the cam and the bucket during this work.  It is hard to make a closure check if there is.

Raw instrument readings are recorded and no converting or calculating is done.  This means any errors on this sheet are from the measuring process.  Otherwise errors might be from measuring or calculating and it is hard to sort out which is which.  Calculations will be done later.


* 2016 Build 295.JPG (181.37 KB, 1024x768 - viewed 46 times.)
Logged
Koncretekid
Sr. Member
****
Offline Offline

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





Ignore
« Reply #2518 on: August 11, 2016, 06:09:56 AM »

Bo,
I always take an additional reading at .040" lift and .050" lift, in order to compare the cam to other cams which are usually rated at one of these two lift measurements.  Of course, you also have to revise the numbers to correspond with crankshaft degrees, as well.
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: 4449





Ignore
« Reply #2519 on: August 12, 2016, 01:35:11 AM »

This is the valve movement curve.  It is based on 0.000 tappet clearance and its values are listed on the left.  A horizontal line is drawn .008 above the zero lift value.  This is the tappet clearance and I always set it at the bottom of the base circle opposite the cam lobe tip.

This displacement data will be used later during the computer analysis.  It is being collected now 'cause the engine is together.  I cannot get it if the motor is apart.


* 2016 Build 296.JPG (193.78 KB, 1280x744 - viewed 46 times.)

* 2016 Build 297.JPG (172.75 KB, 1024x768 - viewed 41 times.)
Logged
Pages: 1 ... 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 [168] 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197   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 November 17, 2017, 10:04:20 PM