Author Topic: Opinions on dyno result  (Read 334 times)

xstian

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Opinions on dyno result
« on: October 19, 2018, 05:56:17 PM »
I've just had my 1kt back from jetting due to a change of exhaust. It's now on martin77 pipes and Tyga cans. It only made 36.1 bhp which is a little disappointing. I don't know what it made before the pipe change.

I thought it would have made over 40bhp, does this seem normal?
« Last Edit: October 19, 2018, 05:59:38 PM by xstian »
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Martin77

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Re: Opinions on dyno result
« Reply #1 on: October 19, 2018, 06:10:47 PM »
Yup, looks a bit low to me, with a very flat curve. It's a shame they didn't do a run with the rpm showing as that would explain a lot more..

I guess all you can do is check the usual things like pv etc.

claw74

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Re: Opinions on dyno result
« Reply #2 on: October 19, 2018, 09:51:50 PM »
Mines got martin pipes and tyyga cans. It showed 51 bhp on dyno.

Bob the B

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Re: Opinions on dyno result
« Reply #3 on: October 24, 2018, 04:46:32 PM »
Yes thatís low. My 2MA is in standard spec and made 46 bhp recently.

tzr-v4

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Re: Opinions on dyno result
« Reply #4 on: October 24, 2018, 08:39:28 PM »
Figures on dyno depend on how the dyno is setup.

Some time dyno are tuned to satisfy the customer !!!

Yes a bit low in fact.
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vinny

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Re: Opinions on dyno result
« Reply #5 on: October 24, 2018, 11:07:40 PM »
I agree
Figures on dyno depend on how the dyno is setup.

Some time dyno are tuned to satisfy the customer !!!

Yes a bit low in fact.
I agree dynos can be wildly different.
I never worry about the  figures too much .
But if you can try to always use the same dyno you should have a good idea if you are making progress.

morepower

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Re: Opinions on dyno result
« Reply #6 on: October 25, 2018, 12:33:32 AM »
I took my little 3MA and had it set up at RJS and it needed jetting as it was way out.. But once it was done it had 47.3BHP on hid dyno.. That is low compared to what I have seen and heard you will expect from a 3MA with pipes and no restriction on the airbox. But after taking it for a ride I really don't care what it says now.. It will have a bit more done over winter with possibly the offset woodruff key and I will check to see if it needs rings etc.. But if I do anything it is going back to RJS to see what gain they say it has... Its not the numbers they give which is important its how it feels and if you do anything it is the gains you get on the same dyno.....

This video I went out and just wanted to get a feel for the bike and run it through the gears either rolling on or just wide open and try and get it to stutter or give me an idea of where it needs more work... But its still quick enough to have fun and it would give the NSR a shock on the straights at least.. The chassis needs more work though.. lol

https://youtu.be/CWTK043YGOs


 

Warwick

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Re: Opinions on dyno result
« Reply #7 on: October 25, 2018, 01:04:09 AM »
I've just had my 1kt back from jetting due to a change of exhaust. It's now on martin77 pipes and Tyga cans. It only made 36.1 bhp which is a little disappointing. I don't know what it made before the pipe change.

I thought it would have made over 40bhp, does this seem normal?

Looks a bit stifled at the top end? Have you checked both Powervalves are opening fully? Is there slop in the PV connecter between the cylinders etc.?
Still Smoking...

Martin77

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Re: Opinions on dyno result
« Reply #8 on: October 25, 2018, 10:41:06 AM »
Also, try and get a run with rpm, as mph curves don't allow you to see the whole picture of what's really going on. mph runs are usually because either a) the dyno man can't be arsed to put the pick up cable on, or the pick up is broken..

xstian

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Re: Opinions on dyno result
« Reply #9 on: October 25, 2018, 07:00:20 PM »
Unfortunately they didn't do an RPM run. I've had my RGV on this dyno before and that was showing over 60bhp so I don't think the dyno under reads.

I'll have a look and see what is going on with the power valves.
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4l04ever

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Re: Opinions on dyno result
« Reply #10 on: October 27, 2018, 11:14:16 PM »
Dynojet dynos tend to read on the higher side, so if it is low on one of these it is very low...
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