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Author Topic: The worlds fastest Weslake.....well maybe!  (Read 68898 times)

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Offline Briz

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Re: The worlds fastest Weslake.....well maybe!
« Reply #105 on: April 22, 2012, 04:16:21 PM »
Got twin VR sensors with a single tooth crank trigger. When cranking, they should fire at alignment, which is at TDC.
But as soon as it starts, it goes crazy.
I've got no more time to spend on it and dont really care anymore, its had its chance, I now have to do something else.

Offline wobblywalrus

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Re: The worlds fastest Weslake.....well maybe!
« Reply #106 on: April 23, 2012, 12:23:30 AM »
Briz, a lot of us are running a simple ignition system and carbs 'cause when something does not work it is a lot easier to diagnose and fix.  We know that EFI is better than carbs and do not consider the benefits to be worth the complication.   

Offline Briz

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Re: The worlds fastest Weslake.....well maybe!
« Reply #107 on: April 23, 2012, 05:30:39 AM »
WW; I'm definitely coming round to that way of thinking!
From what I hear, theres no advantage to EFI in flat-out WOT situations anyway. Some say carbs still have an edge on power.
I thought a bit of laptop tweaking would be easier than getting gas everywhere changing jets. Not so sure now!
I'll still be keeping the wideband oxygen sensor stuff.

Offline RidgeRunner

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Re: The worlds fastest Weslake.....well maybe!
« Reply #108 on: April 25, 2012, 06:10:25 AM »
Got twin VR sensors with a single tooth crank trigger. When cranking, they should fire at alignment, which is at TDC.
But as soon as it starts, it goes crazy.
I've got no more time to spend on it and dont really care anymore, its had its chance, I now have to do something else.

     Any chance that the signal wires are picking up interference on their way back to the ECU?

Offline Briz

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Re: The worlds fastest Weslake.....well maybe!
« Reply #109 on: April 25, 2012, 07:04:05 AM »
Nope; We've done as much as anyone could to shield them short of encasing them in reinforced concrete!

Offline harky

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Re: The worlds fastest Weslake.....well maybe!
« Reply #110 on: April 26, 2012, 04:14:02 AM »
hi all
just read the whole thread , great read and build
totally unrelated , I worked on Weslake engines in SAAB rally cars in the late 70s thay came to Australia
in  rally cars driven by STIG BLOOMQUIST and were the equivilant of ford BDA engines . they made over 200 hp ( on carbys) and @ that time was quite the thing . One of the engines was left in Adelaide and is in a very plain SAAB 99 ----a real sleeper
So Weslake was @ all sorts of things
I run an old GPZ on the salt in OZ with motec ---- not too fast yet but working on it
looking forward to the riding report
cheers
harky
old mechanic
getting slower , but still interested in anything that goes FAST

Offline 38flattie

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Re: The worlds fastest Weslake.....well maybe!
« Reply #111 on: April 26, 2012, 05:15:10 AM »
I finally read this whole thread.

Great build with a lot of detail. Good luck!
With sufficient thrust, pigs fly just fine. However, this is not necessarily a good idea. It is hard to be sure where they are going to land, and it could be dangerous sitting under them as they fly overhead. -- RFC 1925

You can't make a race horse out of a pig. But if you work hard enough at it you can make a mighty fast pig. - Bob Akin

http://www.flatcadracing.org/
http://youtu.be/89rVb497_4c

Offline oz

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Re: The worlds fastest Weslake.....well maybe!
« Reply #112 on: April 26, 2012, 10:34:10 AM »
I had to move reg rec away from ecu and that did the trick for me, I think you could/should  run single trigger they may be interfering with each other and time it from that as an offset beetween cylinders.
Just my ten peneth but may be worth a go before you start a major re work.
Newcastle born and bred a City built on Coal and Steel and a people built of stronger stuff

Offline Briz

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Re: The worlds fastest Weslake.....well maybe!
« Reply #113 on: May 08, 2012, 06:18:17 PM »
Well the fuel-injection is gone. Sold the microsquirt & a heap of other efi stuff on ebay last week most of which made good money. Which helps. :-D
Had the BBC film crew round last thursday. Had to do something on the bike for them to film, so i took off the timing cover & set about machining it for HD ignition parts. They got bored with milling and left halfway through.
A bit more work than envisaged, but its in there:




These are the carbs I got for it:


Need to get this all installed. Conflicting pressures (customers!) Not a lot of time.

Offline saltwheels262

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Re: The worlds fastest Weslake.....well maybe!
« Reply #114 on: May 08, 2012, 06:39:50 PM »
what brand ignition ?
I don't recognize the carbs , either.

franey

bub '07 - 140.293 a/pg   120" crate street mill  
bub '10 - 158.100  sweetooth gear
lta  7/11 -163.389  7/17/11; 3 run avg.-162.450
ohio -    - 185.076 w/#684      
lta 8/14  - 169.xxx. w/sw2           
'16 -- 0 runs ; 0 events -- made a 2 state change in ZIP codes

" it's not as easy as it looks. "
                            - franey  8/2007

Offline Briz

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Re: The worlds fastest Weslake.....well maybe!
« Reply #115 on: May 08, 2012, 06:51:29 PM »
I bought a Twin-Tec module & coil. Similar to Crane Hi-4E. Can set it for 9500 rev limit.
Carbs are late 80s Screamin' eagle Keihins. Never that great on the street, but should be fine for this. Smaller than S&S's and  about a sixth of the cost!

Offline saltwheels262

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Re: The worlds fastest Weslake.....well maybe!
« Reply #116 on: May 08, 2012, 07:11:17 PM »
okay. my twin tech does not have a module, self contained.

maybe the carbs are from an xr motor? flat tracker? ( with a clamp on air filters ).
bub '07 - 140.293 a/pg   120" crate street mill  
bub '10 - 158.100  sweetooth gear
lta  7/11 -163.389  7/17/11; 3 run avg.-162.450
ohio -    - 185.076 w/#684      
lta 8/14  - 169.xxx. w/sw2           
'16 -- 0 runs ; 0 events -- made a 2 state change in ZIP codes

" it's not as easy as it looks. "
                            - franey  8/2007

Offline Briz

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Re: The worlds fastest Weslake.....well maybe!
« Reply #117 on: May 09, 2012, 04:03:06 AM »
Couldn't use any of the self-contained type ignitions; they will all only work on a 45 degree motor - this one is 50 degree. By making the rotor with the cutouts at the right angle apart, this one will work OK.
The carbs were offered by HD as a performance part in the late 80s & 90s for evos. Many folks used them to get around cold weather carb-icing experienced with the stock CV carb. But they have only 2 metering circuits and are hard to fine-tune for good street manners. A thunderjet kit helps. They're related to the stock 40mm Keihins found on late shovels and early evos.

Offline Vinsky

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Re: The worlds fastest Weslake.....well maybe!
« Reply #118 on: May 09, 2012, 12:45:53 PM »
Dynatek's DS6-2 is a single fire ignition for 45 Harleys, but there is enough adjustment in the modules to get 50 degrees out of  them. I'm using this setup on my Vincent project.
John

Offline wobblywalrus

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Re: The worlds fastest Weslake.....well maybe!
« Reply #119 on: May 10, 2012, 12:05:56 AM »
Briz, those carbs look good.  One thing I do is to connect a clear small diameter breather hose between the top of the float chamber and the bottom of the chamber.  The level of the fuel in the little hose corresponds to the fuel level in the float chamber.  Then the bike is run at full throttle for a few seconds on the dyno.  The fuel level might drop a small amount at first then it should hold steady at the proper level.  The level dropping and staying down is a sign the float valve or fuel cock is too restrictive.

The reason I tell you this is some fuel systems that work OK on the street cannot flow enough for the sustained open throttle madness that is LSR.  It is an easy problem to fix if it is detected early.

The float bowl venting system should not be altered when you do this.  Sometimes I put a "T" the float bowl vent hose and connect the top of the little hose to it.  I pull out the float bowl drain screw and hook the bottom end of the little hose to it.  All of this is taken off after the dyno run.