That explains more. Then yes, you need it tuned. The 5 to 10 nonsense still does not apply. If you want it spot on then you need a unit like a TTS or similar and have a COMPETENT tuner Dyno it. If not then IMHO I would suggest this,

http://www.revperf.com/Precision/index.html

This will get you VERY close without a Dyno.

 

Yes there is V-tuning Smarttune etc. But for a shop to do it would cost big money. You'd have to be willing to pay shop rate for a guy to ride your bike and data log. The problem with smarttune is that while you re data logging, you could very possibly be running your bike WAY out of tune, which could put more wear on it than the dyno would. So if Smarttuning you'd better hope your starting MAP is pretty damn close to what your build is. My guess is the shop in question had a dyno and either it was an older one and didn't have load control on it or they didn't know how to use it so they sold it.

I full tune my bike 3 or 4 times a year. (i'm always throwing something new in it, just because) and I can tell you it doesn't add 5000 - 10000 miles on it. If so, hell, I have about 120,000 miles on my bottom end.

 

To be fair to the shop they didn't know if I had a carb or EFI. I wasn't riding my bike that day. The reason I brought up the 5k to 10k worth of wear when doing dyno runs claim. Is that if you look at both the Dunlop and Metzeler catalogs they claim dyno runs could lead to tire failure.

 

A rear Dunlop isn't good for much more than 10,000 miles. So if that were the case, this theory would mean that a dyno tune would use up at least half the wear of the tire.

 

Just an article related to dyno tunes. I have no opinion one way or the other.

http://www.harleyhelp.com/dyno.html

 

Thank you for sharing that. My opinion is I don't want up to 10rwhp sitting on the table when I increase the engine breathing capacity, I want it running perfectly and getting the best mileage.

Tuners DO increase hp because the stock ECU, and even Stage 1, do not optimize the A/F ratios and ignition timing.

 

Ok, but dont loose sight of the fact that engines just arent that sensitive to AFR and timing.

http://www.daytona-sensors.com/tech_tuning.html

This article does a good job of showing just how insensitive engines are - especially to timing - the charts illustrate this well.

Of course this shouldnt be too surprising to those of us whos first HD had a carburettor and single fire electronic ignition was a novelty.

 

It took you 8 months to selftune your bike, i'd assume that means fine tuning your A/F anf timing tables. If you say that engines are not that sensitive to airfuel and timing, why did it take so long to tune your bike? I'm confused on that. Engines produce the most power between 12.5 and 13.0 A/F and are most efficient at 14.7 A/F, that doesn't mean they can be anywhere in there at all the RPM and throttle positions.

 

That's an interesting web site to say the least.

However, when I see statements like these:

Today the majority of Harley riders are well incomed, cheap ***, penney pinching, belly aching Morons.

Even all you people on this website. All you are here for is to try to get something for nothing, something for free!
For years I have operated this website on the theory that - the more people that try to do their own work, the more people there will be screwing up their own bikes and then they will finally bring it to me to have it done right - and that theory has always held true, but now I'm just so sick of all of you idiots that cannot appreciate a skillful, quality job and all you do is gripe!

I'm tired of it and I'm not helping any of you anymore!
HarleyHelp.com is done!

I question his judgement. Maybe he had a bad day. I note that the post was at 2:30 a.m. so maybe he'd had a few adult beverages and decided to vent.

As to dyno tuning: I've been around dynos for autos and bikes for years. I have been fortunate to have my vehicles tuned by extremely competent and respected tuners is my area. They have never failed to optimize performance of a given engine.

Does everyone need and dyno tune? No. But at the very least I would want to verify a/f ratio after making even minor mods. I can get a baseline dyno showing a/f ratio for about $50. Cheap peace of mind I'd say.

 

Yeah it does.

A/F can be as low as 11.5 and it will only cost you about 3% TQ.

Timing can be plus or minus 5 degrees and it will only cost you 1% TQ.

I put it to you that these percentages are so low that a dyno cant measure them accurately, and you wouldnt be able to measure them yourself via seat-of-the-pants when riding on the street.

It took me 8 months to tune my bike because I dont get to the drags that often, Eastern Creek is nearly 2 hours drive away and I just dont have the time with work etc. When your bike gets to 100 mph in less than 10 sec the opportunities for WOT testing arent that often if you wanna keep your licence. In 8 months I am up to Version 24 of my tune. Quite a few of those versions didnt change tune at all, they were changes to try to stop the starter kickback, throttle progressivity, warm up. Anyhoo, long story.