The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: orabanda on 19.08. 2010 06:50
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Hi All,
My RGS replica (62 Super Rocket), is still cooling down, after it's first time on the dyno.
It will have a second (and final) run in a couple of weeks time, after I get some leaner throttle slides from Hitchcocks.
(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi302.photobucket.com%2Falbums%2Fnn82%2Forabanda%2FP1030510.jpg&hash=fb66c5983bfd8c9fb9fa4898536aa37e285f0031)
(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi302.photobucket.com%2Falbums%2Fnn82%2Forabanda%2FP1030512.jpg&hash=3a78c55850c01717d32b0c3ac914725784495a7a)
So, how did it go?
(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi302.photobucket.com%2Falbums%2Fnn82%2Forabanda%2FRichardArgusRGSReplica.jpg&hash=41db689af7bc04329eaeea2fa3d02c81ae0bc80a)
About 6 hp better than an iron head GF so far, and I reckon there will be a little bit more, when the correct (leaner) slide is installed.
It started with the standard #3 slide (and a K & N element in the air cleaner, but the mixture was way too rich. The leanest slide I had was a 3 1/2, which improved (leaned) the mid range. However, it needs to be at least a 4 (maybe 4 1/2).
The needle is cutrrently at its lowest (leanest) position, but we expect to raise it a notch or two once the slide is changed.
Main jet is perfect (spot on mixture) at 420.
Needle jet is best at 106.
Started timing at 34 BTDC. (At 35 or greater the engine with ping).
This gave 26 HP (rear wheel).
the best timing setting is 32 btdc. Power goes up to 28 HP, torque increases by 10 ft lb, and is a 3,000 rpm instead of 3,200 rpm when timing was more advanced.
retarded timing to 30 BTDC, but HP dropped to 26, and max torque drcreased.
Engine no longer pings, and pulls like a choir boy!
Will post final curve after next run (when slides arrive).
Richard
The Kalgoorlie Kid
Joke:
A man asked a wise old American Indian chief "What is your wife?s name?"
He replied, ?She called Four Horse?.
The man said, ?That?s an unusual name for your wife. What does it mean??
The Old Indian answered, ?It old Indian Name. It means ?
? NAG, NAG, NAG, NAG!"
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Interesting stuff Richard, whats in the engine of this one, cam/compression etc ?
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Brian
Big valve head
8.5:1 comp
357 cam
389 carb
standard K2F, RH pot 2 degrees advanced on LH pot - one day I will grind cam ring & make them zero variance
Inlet = 0.0080 clearance
Ex = 0.010"
K & N air cleaner element
Suzuki clutch
SRM pushrods (steel)
My own oil filter system
'66 Lightning front brake (Yippee - it stops!!)
http://i302.photobucket.com/albums/nn82/orabanda/RGSClutch2-2.jpg
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What were you getting from an iron head GF?
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A10boy,
This is Mario's A10 (see my thread re Sunday's ride to menzies):
(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi302.photobucket.com%2Falbums%2Fnn82%2Forabanda%2FP1020104-2.jpg&hash=9bf19d1304085b7e410f61da9087d235ba642b1e)
This is the test results:
(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi302.photobucket.com%2Falbums%2Fnn82%2Forabanda%2FMarioCudiniGlodenFlash1955run1.jpg&hash=363919de397622099775f598d1a22efbe7f919a3)
7.25: pistons
356 cam
Monobloc
Inlet = 0.010"
Ex = 0.016"
Compression = 143 psi LH, 146 psi RH
Best timing setting = 30 degrees BTDC
This is my '54 flash
(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi302.photobucket.com%2Falbums%2Fnn82%2Forabanda%2FP1010170_resize.jpg&hash=2ae8ecc3365a26b463374d8b85eb4ec8a67be6f6)
(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi302.photobucket.com%2Falbums%2Fnn82%2Forabanda%2F54A10resizegraph.jpg&hash=d31922215d40f6dafab6ad1c5a5bd1a12c981ccb)
7.25: pistons
356 cam
276 carb
Inlet = 0.010"
Ex = 0.016"
Compression = 145 psi LH, 145 psi RH
Best timing setting = 30 - 30.5 degrees BTDC. No variance between pots (I did a good job of grinding cam ring).
Richard
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Great stuff Richard. Can you let us have some info on that delicious looking clutch? Clearly it's been adapted somehow to fit on a BSA gearbox mainshaft taper.
Are the friction plates constructed with friction pads on steel plates or are they full friction material like Bob Newby's clutch used on his belt drives? I can't quite make it out on the photo although the clutch basket looks like aluminium. Is it?
Cheers
Alan
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Clutch is a modified Suzuki GS550, using alloy sprocket, and standard Suzook plates.
This is the modified Suzuki PE400 clutch I am putting on my latest project; 1960 SR - should be running in a few weeks
http://i302.photobucket.com/albums/nn82/orabanda/P1030037.jpg
http://i302.photobucket.com/albums/nn82/orabanda/A10beltdrive2PE400.jpg
Richard
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Dyno testing was free at the Farmyard Party this year. Bob considered briefly letting them have a go with his B31 but decided he'd rather ride home on it in one piece. 1946 rigid construction. So its been very interesting to read this when 'real' bikes have been tested, thank you.
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Richard,
Have you tried opening the valve clearances to .010" & .012"?
Eddie Dow recommended these clearances for max HP in his tuning tips.
It would be interesting to see if it is true.
He also mentioned increased noise.
Trev.
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Trev,
Good suggestion!
I will do that when the RGS replica goes back on the dyno.
I could always do with a bit more of that delicious noise!
Richard
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It's very interesting to note that an iron head GF is best timed at 30 / 30.5 degrees BTDC when using the following set up.
7.25: pistons
356 cam
Monobloc
Inlet = 0.010"
Ex = 0.016"
I set mine from the book, which was [from memory] 33 degrees BTDC and it runs very sweet. I am now wondering whether I should try it at 30.5 to see what happens. Maybe I should leave well alone. *conf*
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andy,
My experiences are that 33 degrees is OK, but not the absolute best for the alloy head engine.
Bear in mind that I am using a strobe light; I am finding that there is sometimes variance of up to 2 degrees of the timing, when setting by feeler gauge, and then checking with strobe; operator error & technique must be the reason.
Now I set with feeler gauge for initial start-up, then use the strobe for final setting.
regards,
richard
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Got a couple of questions Richard, firstly I know 50% less than bugger all about dyno's so.......
How do you know what the mixture is doing at a particular throttle opening or rev range, do you have a exhaust gas analyzer up its pipe?
I believe that the dyno has a brake or rolling resistance effect to simulate wind resistance or drag as would be expeienced if the bike was actually on the road, does this brake effect increase as the revs increase ? if the bike was actually on the road the wind resistance would be greater at higher revs as you would be travelling faster. Also does the weight of the bike and rider factor into the brake calculation ?
Have you ever done a dyno comparison between twin pipes and a siamese system ?
I'll shut up now and leave you alone *eek*
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Hi Brian,
You are correct; there is a gas analyser shoved up the pipe(s). Remember my previous threads about three of the A10's having induction bias?
It stands out like a nun at a nudists convention, when you can measure the mixture out of each pot.
The dyno is always measuring this info, and the screen shot Ray tunes off, plots air / fuel mixture ratio, against HP.
It is the 6th column from the left ("Power Petrol"). The ideal ratio for carburated engine is 12 -12.5. and 13:1 for fuel injected engines (leaner).
After the first run, he can see how close the metering stages of the carby is (Ie air mixture screw, pilot jet, needle and throttle slide, and main jet.
Therefore, he will often make two changes after the first run; ie needle AND main jet.
Here is the first run from my RGS replica:
Note how rich it was (Power Petrol) at 10:1, all the way up to the main jet, which is OK at mid 11's.
He does the run in third gear.
Keep an eye on the torque figures (4th column on left), and their relationship to RPM.
Customer Richard Argus
1CN383 BSA RGS Replica 1962
Ramp-rate: 090 Tacho ratio: 58.0:3000 Graph: 1CN383.0001 19-08-10 / 11:46:28
Dynamometer Correction Information
Ambient Temp. 17.0 degC Humidity 43.0 % Press. 1022.00 mbar
Inlet Air Temp. 15.4 degC Corr. used ATMC2 0.950 Extra corr 1.000
Inertia lb Dynamometer 125.08 Drive-train 44.09
Speed Tacho [Rat] [b]Power[/b] T.E. IAT HS AFR Lambda CO2 CO Vac/Bst HC Tmp 01 Tmp 02 O2 NOx Comments
km/h rpm HP lb degC Petrol Petrol % % (Atmos) ppm degC degC % ppm
52 2690 7.0 81 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
54 2793 9.2 103 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
56 2897 12.0 130 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
58 3000 13.4 140 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
60 3103 14.5 145 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
62 3207 16.0 156 15.3 10.2 0.70 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
64 3310 17.0 161 15.4 10.2 0.70 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
66 3414 18.0 165 15.4 10.4 0.71 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
68 3517 19.0 168 15.4 10.7 0.73 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
70 3621 19.4 167 15.4 10.4 0.72 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
72 3724 19.4 163 15.4 10.4 0.72 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
74 3828 20.0 163 15.4 10.5 0.72 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
76 3931 20.0 159 15.4 10.3 0.71 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
78 4034 20.3 157 15.4 10.2 0.70 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
80 4138 20.4 154 15.4 10.1 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
82 4241 20.5 151 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
84 4345 21.0 151 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
86 4448 21.3 149 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
88 4552 21.5 148 15.4 10.1 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
90 4655 22.0 147 15.4 10.1 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
92 4759 22.3 146 15.4 10.0 0.69 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
94 4862 22.8 146 15.4 10.1 0.70 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
96 4966 23.1 145 15.4 10.2 0.70 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
98 5069 23.5 145 15.4 10.3 0.71 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
100 5172 24.2 146 15.4 10.3 0.71 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
102 5276 24.8 147 15.4 10.6 0.73 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
104 5379 25.3 147 15.4 10.8 0.74 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
106 5483 25.8 147 15.4 11.1 0.76 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
108 5586 25.9 145 15.4 11.2 0.77 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
110 5690 26.4 145 15.4 11.4 0.78 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
112 5793 26.6 143 15.4 11.4 0.78 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
114 5897 26.8 142 15.4 11.6 0.79 0.00 0.00 -0.0 inHg 0 -252 -252 0.00 0
Now, here was the final run for the day. Note the improvement to the "Power Petrol" ratio. However, it is still too rich from about 3724 rpm to 5276, which will be corrected with the leaner slide.
Also note the broader torque figures, and at lower rpm. The changes were: leaning the mixture and retarding the timing to 32 degrees.
Ambient Temp. 17.0 degC Humidity 43.0 % Press. 1022.00 mbar
Inlet Air Temp. 16.8 degC Corr. used ATMC2 0.953 Extra corr 1.000
Inertia lb Dynamometer 125.08 Drive-train 44.09
Speed Tacho [Rat] Power T.E. IAT HS AFR Lambda CO2 CO Vac/Bst HC Tmp 01 Tmp 02 O2 NOx Comments
km/h rpm HP lb degC Petrol Petrol % % (Atmos) ppm degC degC % ppm
48 2483 9.1 115 16.9 13.9 0.95 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
50 2586 11.9 144 16.8 13.3 0.92 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
52 2690 12.9 150 16.9 12.9 0.89 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
54 2793 13.7 153 16.9 12.4 0.85 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
56 2897 14.7 158 16.9 12.3 0.85 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
58 3000 15.4 160 16.9 12.2 0.84 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
60 3103 16.6 167 16.9 12.0 0.82 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
62 3207 17.4 169 16.9 12.0 0.82 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
64 3310 17.8 168 16.9 11.9 0.82 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
66 3414 18.7 171 16.9 12.0 0.83 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
68 3517 19.1 170 16.9 11.8 0.81 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
70 3621 19.3 166 16.9 11.6 0.80 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
72 3724 19.8 166 16.8 11.5 0.79 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
74 3828 19.8 162 16.9 11.3 0.78 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
76 3931 20.1 160 16.9 11.3 0.77 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
78 4034 20.2 156 16.9 11.2 0.77 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
80 4138 20.4 154 16.9 11.2 0.77 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
82 4241 20.6 151 16.9 11.0 0.75 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
84 4345 20.8 149 16.9 10.8 0.74 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
86 4448 21.0 148 16.9 10.7 0.73 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
88 4552 21.3 146 16.8 10.6 0.73 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
90 4655 21.6 145 16.9 10.6 0.73 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
92 4759 22.0 144 16.9 10.7 0.73 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
94 4862 22.5 145 16.8 10.9 0.75 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
96 4966 22.9 144 16.9 11.0 0.76 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
98 5069 23.6 145 16.9 11.1 0.76 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
100 5172 24.2 146 16.9 11.3 0.78 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
102 5276 24.8 147 16.9 11.5 0.79 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
104 5379 25.2 147 16.9 11.7 0.81 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
106 5483 25.7 147 16.9 12.0 0.82 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
108 5586 26.3 147 16.9 12.2 0.84 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
110 5690 26.5 146 16.9 12.3 0.84 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
112 5793 26.7 144 16.9 12.3 0.85 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
114 5897 27.1 143 16.9 12.4 0.85 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
116 6000 27.3 142 16.8 12.5 0.86 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
118 6103 27.5 141 16.9 12.6 0.86 0.00 0.00 0.0 PSI 0 -250 -250 0.00 0
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Good stuff Richard, thanks for putting that all up.
I gather you are aiming to have a constant air/fuel ratio through the complete rev range, I would have thought that the mid range would benefit from being slightly richer as this is where most of your acceleration takes place. A modern engine would either inject a slightly richer mixture at this point or if using carbies would most likely have pumps (acceration pumps). My Guzzi for instance has 40mm delorto's with pumps and they squirt quite a stream of fuel down its throat when you twist the throttle.
I find this very interesting and wish I could look over your shoulder. To be able to see just what the engine is doing and being able to see the results when changes are made must be very satisfying plus when its all done you can be confident your bike is performing as well as it possibly can.
Just going off track for a minute, I see you have a shed full of "chook chasers" as well. I had mostly Suzuki's in my younger day, TM's, TS's, RM's etc. Anyway in 1974 I bought a new 250cc VR Montesa Cappra, this thing was unreliable and difficult to live with, but, it was the most poweful 250cc I have ever owned or ridden to this day. We lined it up against SC500 Yamaha's, RM370 Suzuki's etc and none of them could even get close, it was a truly amazing bike when it went !
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Hay you two, I had a '69 Monty GP MX 360 that would shred tyres on the tar. I was only 11 at the time, yeee harrr. Try to get one now, $16K +
Cheers
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For those that might be interested. Eddie Dow
Have you tried opening the valve clearances to .010" & .012"?
Eddie Dow recommended these clearances for max HP in his tuning tips.
http://bsa-a10.hailwood.com/tt11.html Eddie twins tuning tips.
John
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Jeez Muskrat, a 360 Cappra at 11 years old, I only had a rotten 125cc James. I always vowed I would never own a Villiers engined bike again after it and with the exception of a Greeves Starmaker I never did.
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Don't complain Brian - I was seventeen before I was granted an NSU Quickly ( 50 cc of unbridled power!!!) , took several years a Golden Arrow and a Flash to regain some street cred which I blew with the purchase of a Reliant - you guessed it, not a Scimitar, at least it wasn't yellow.
Did have a lot of fun in that Regal though, imagine a Morgan in permanent reverse *smiley4*
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I didn't know much about tuning back then. Once I got a push to clutch start her (no kickstart) she fired so I pulled the clutch so my mate could jump on. Gave it a fist full and dropped the clutch. Both of us went over the handlebar. It was running backwards. Doh.
Cheers
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Don't complain Brian - I was seventeen before I was granted an NSU Quickly ( 50 cc of unbridled power!!!) , took several years a Golden Arrow and a Flash to regain some street cred which I blew with the purchase of a Reliant - you guessed it, not a Scimitar, at least it wasn't yellow.
Did have a lot of fun in that Regal though, imagine a Morgan in permanent reverse *smiley4*
did this ever happen to ya bill ?
http://www.youtube.com/watch?v=130OVZcMEcA
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did this ever happen to ya bill ?
No I managed to keep it off it's sides, but often it was on two wheels even with a full crew of mates.
After I sold it, it did the " I don't need a front wheel " bit so I heard, it did brake a rear spring once which I managed replace the wrong way around, sort of crabbed my way around for a while, although this was not the cause of the "Old Berwick Bridge incident" with three mates keeping all three wheels grounded I caught the kerb as we traversed across the bridge, this resulted in the car (HA) swinging around until the front wheel also was up against the kerb and we crabbed across taking up all the road, has to be said it's a narrow bridge though.
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Just found this thread- super info - does anyone have Dyno figures for the A65 Lightning or Thunderbolt? I just wanted to see where the power peaks with the high state of tune. I much prefer my A10 GF much softer state of tune and my hands and feet don't go numb with the vibration!
Thanks
Nigel