Dyno-tastic results!

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alan
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Post by alan »

Pete.L wrote:
alan wrote:Thanks Pete just took plugs out there black so its running rich i believe.
Has the mixture screw or anything else been played with? If not I can only think the new pipe configuration might be upsetting the flow and richening it up. Also check the choke cable is sitting properly in the carbs at the carb end. I take it both the plugs are sooty and not just one of them.

Pete.l
Hi Pete
i dont think its been messed with as it was totally standard when i got it nothing was changed im only the second owner and modder.

I hav'nt checked the choke but will do

The front was Sooty and the rear was Sweep :wink: :lol: :lol:

no both was.
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Pete.L
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Post by Pete.L »

The front was Sooty and the rear was Sweep
Nutter :lol:
If the choke's ok a dyno run would be a good step forward. Hopefully a sticking cable is the answer and away you go again. If not a dyno run will tell you where it's running rich and what needs to be done/changed. You might get away with just a twiddle on the fuel mixture but more than likely a jet kit will be needed to get a good result across the rev range.
Have a play and see how you get on.

Pete.l
alan
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Post by alan »

Thanks Pete for all your help will have a mess about i'm just abit nervous of putting my pride and joy on a dyno. You dont think the K & N could be making it this rich do you?

After all the money i spent i carefully and sheepishly told my wife i needed a jet kit (mops up blood from nose) but to my surprise she's going half :lol: :lol: :lol: :lol: :lol: :lol:


aint married life just wonderful :wink:
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Pete.L
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Post by Pete.L »

You don't think the K & N could be making it this rich do you?
No mate, definitely not. The K&N filters are slightly higher flowing than standard and often leave the mixture a bit lean in places that's why I suggested raising the needles with a 0.6 mm washer to richen it up again. Now you've had a look at the p[lugs and they are a bit sooty (and Sweep :D ) I think it's more to do with the length of the high rise pipes you've made. it's quite common for high rise pipes to actually reduce power rather than enhance the performance, due to the extra length in the connecting pipes causing reverse pressure waves in the the exiting gas flow. I think that's a more likely cause for the poor performance. You can normally get around this by re-jetting to a slight leaner setting (with the loss of a few HP) but you have enough to play with so being 3 or 4 HP down wont make a difference once it's running cleanly. Actually you are probably down more now with it running rich than what you will be after a re-jet.
After all the money i spent i carefully and sheepishly told my wife i needed a jet kit (mops up blood from nose) but to my surprise she's going half
Sounds like you've got a keeper there :wink:
I've just told my wife I've blown my rear shocker and I'm going to have to buy a new one and she hasn't come back down yet :eek2

Pete.l
alan
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Post by alan »

Thanks again Pete one more question for you

If you was in my position what would you do?
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Pete.L
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Post by Pete.L »

Personally I don't like the Dyno Jet needles on a Vtwin.
The finish on some of then is rough and I think they prematurely wear the carbs out I.E they grind the seating to an oval.(if you watch how they bounce up and down so dramatically when blipping the throttle in the lower revs you'll understand) I've seen it on a couple but maybe someone who does it for a living will have a better idea. When you look at the Honda one the finish on them is so silky smooth you could almost believe they were frictionless.
In the ideal world I would like a Honda needle which was as adjustable as a Dyno jet one, then I would be happy.
For your solution It might be worth while seeing if you can retain the original needles and just change the mains but with out putting it on a Dyno you won't know I'm sure Roger did this for Ben at Revolution racing maybe he'll have a better idea on feasibility.
Either way, I'm sure the Old Girl can take a few runs on the Dyno with out popping its cogs. That's got to be the first port of call. If it's only rich in the bottom end it might not need jetting at all.

Pete.l
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sparrowlegs
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Post by sparrowlegs »

Mines been in today for front CCT..carb balance and a dyno run...slightly gutted at the results tho.............101.64 BHP at the rear wheel
Video will be on as soon as youtube finishes faffin with it lol
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sparrowlegs
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Post by sparrowlegs »

video :D
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cupasoop
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Post by cupasoop »

sparrowlegs wrote:slightly gutted at the results tho.............101.64 BHP at the rear wheel
err, thats actually pretty good if thats at the wheel. About 108 - 110 bhp in real money.
Rich.

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sparrowlegs
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Post by sparrowlegs »

results came in at
run one 99.50
run two 101.64
run three 101.25
run four 100.86
all at the rear wheel
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SILVER ZIPPER
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Post by SILVER ZIPPER »

Don't get to depressed Sparra.
That's plenty of power for a girl. :P
I HATE IT WHEN I HAVE TO PUT IT AWAY........
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sparrowlegs
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Post by sparrowlegs »

Never enought power for this girl..i is a big lass..need big power...ohh and big pistons lol :wink:
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orangestorm
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Post by orangestorm »

BIG pistons !!!!!! next you'll be wantin high compression n big revs :oops: :oops:
Jaglifter
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Post by Jaglifter »

Nice bike Sparra. Good sound. 101bhp is in the ball park.
She's my idea of beauty and thats what I ride.
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sirch345
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Post by sirch345 »

sparrowlegs,
I like the video :!: :D especially the flames shooting out the back, it sounded ace 8)
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