Tuning or not after installing slip ons?

S

snerkler

Registered User
I was under the impression that you didn't have to tune the engine if you were installing slip ons only, however after reading the comments in this video they say that you should tune as it can run hot and cause blueing. Also it's mentioned that you will get deceleration pops (I assume this is what we'd refer to as overrun pops).
https://www.youtube.com/watch?v=k3zl_7G6th8&list=PLO3SwPOQaiglIFncg_WmHDsaPVV56Nq6M&index=38&t=5s


What's folks thoughts on this, should you tune or not if you install slip ons only? Would the M8 engine have as much of an issue with running hot as it's a cooler engine in the first place?

Any thoughts would be appreciated.
 
Re: Tuning or not after installing slip ons?

Hi Toby I put my M8 on the rolling road at Dyno Tune near Garstang the difference is unbelievable i have run slips ons without a tune before but in my opinion i would have the ECU reset
 
Re: Tuning or not after installing slip ons?

Army said:
Hi Toby I put my M8 on the rolling road at Dyno Tune near Garstang the difference is unbelievable i have run slips ons without a tune before but in my opinion i would have the ECU reset
Click to expand...
Thanks for the info. Can you have the ECU reset at the dealers or are you best off going to an indy? Any idea of costs, and whether this would affect insurance over and above adding slip ons?
 
Re: Tuning or not after installing slip ons?

snerkler said:
Thanks for the info. Can you have the ECU reset at the dealers or are you best off going to an indy? Any idea of costs, and whether this would affect insurance over and above adding slip ons?
Click to expand...

It will affect warranty.


Sent from my iPhone using Tapatalk
 
Re: Tuning or not after installing slip ons?

snerkler said:
But slip ons on their own won't? That's made my mind up then, no tuning ;)

Thanks for the help.
Click to expand...

That?s what I?m doing. Slip ons until next August then a Power Vision tuner.


Sent from my iPhone using Tapatalk
 
Re: Tuning or not after installing slip ons?

snerkler said:
should you tune or not if you install slip ons only
Click to expand...

If you want your new engine to run better and cooler then yes you should. Every new engine comes from the factory with the air/fuel ratio set so that it complies with the emission regulations. This is what causes the excessive heat as the stock tune is set to 14.6:1 which is widely accepted as stoichiometric for todays pump fuels. As Army says, once the air/fuel ratio has been addressed the difference in performance and combustion temperature is enormous. In my opinion every engine out there should be competently tuned - there are no negatives to doing this.

snerkler said:
Can you have the ECU reset at the dealers or are you best off going to an indy?
Click to expand...

As you become more experienced with your new bike you'll find that you're better off going to an independent for pretty much everything. Dealer tuning facilities are nothing more than downloading a tune from the SE database and flashing that to your ECM. ALL of the SE tunes are designed around the aforementioned emission regs so you're not going to gain much also they are designed for engines that have had SE parts fitted. If you have a major component such as an exhaust system from another manufacturer then the SE tune will not be accurate. Currently the best tuning device is without a doubt the Power Vision. The dyno centre that Army mentioned is the same one I use and in my experience over the last ten years is the best in the country. They charge ?180 for a custom tune and there are options for either buying your own Power Vision or buying a license from a Dynojet dealer and using their license. The latter is what most of my customers do as it's a lot cheaper plus the vast majority of riders are not interested in all of the functions available within the Power Vision. Many of them that have been purchased end up as ?500 garage ornaments ...
 
Re: Tuning or not after installing slip ons?

I dealer offered me a remap but it was only ?100 more to have it on the rolling road for 3 hours and the results are amazing
 
Re: Tuning or not after installing slip ons?

Bav said:
That?s what I?m doing. Slip ons until next August then a Power Vision tuner.


Sent from my iPhone using Tapatalk
Click to expand...
I think I'm not going to 'mess' too much whilst the bike's under warranty. I'm not bothered about performance enhancements I just want it to sound better, as long as the exhaust system doesn't completely discolour and look awful. For example, it was 'normal' for the headers on the GS to discolour (min was completely stock but still discoloured, see below), I wouldn't want the chrome on my harley to look this bad.

DSC00326 copy by TDG-77, on Flickr


The next thing is deciding which slip ons to get. I really need to listen to some in person but haven't had the opportunity, and haven't found anyone with the ones I'm looking at. From watching youtube videos (not great I know) the Vance and Hines Twin Slash are top of my list. I like the sound (from what I can tell from listening on YT), I like the look and they are within budget. I also like the TAB performance BAM sticks with 2.5" baffles but they are more expensive and I've not found anywhere in the UK that stocks them yet meaning the price will be considerably more after shipping and tax.

Fast Lane said:
If you want your new engine to run better and cooler then yes you should. Every new engine comes from the factory with the air/fuel ratio set so that it complies with the emission regulations. This is what causes the excessive heat as the stock tune is set to 14.6:1 which is widely accepted as stoichiometric for todays pump fuels. As Army says, once the air/fuel ratio has been addressed the difference in performance and combustion temperature is enormous. In my opinion every engine out there should be competently tuned - there are no negatives to doing this.



As you become more experienced with your new bike you'll find that you're better off going to an independent for pretty much everything. Dealer tuning facilities are nothing more than downloading a tune from the SE database and flashing that to your ECM. ALL of the SE tunes are designed around the aforementioned emission regs so you're not going to gain much also they are designed for engines that have had SE parts fitted. If you have a major component such as an exhaust system from another manufacturer then the SE tune will not be accurate. Currently the best tuning device is without a doubt the Power Vision. The dyno centre that Army mentioned is the same one I use and in my experience over the last ten years is the best in the country. They charge ?180 for a custom tune and there are options for either buying your own Power Vision or buying a license from a Dynojet dealer and using their license. The latter is what most of my customers do as it's a lot cheaper plus the vast majority of riders are not interested in all of the functions available within the Power Vision. Many of them that have been purchased end up as ?500 garage ornaments ...
Click to expand...

Army said:
I dealer offered me a remap but it was only ?100 more to have it on the rolling road for 3 hours and the results are amazing
Click to expand...
Thanks for the info, very interesting. In an 'ideal' world I would have it tuned to run better, but after forking out for the bike I don't have a lot of funds available, plus I'm not wanting to lose warranty hence me now deciding to put a tune on the back burner for now.
 
Re: Tuning or not after installing slip ons?

snerkler said:
Thanks for the info, very interesting. In an 'ideal' world I would have it tuned to run better, but after forking out for the bike I don't have a lot of funds available, plus I'm not wanting to lose warranty hence me now deciding to put a tune on the back burner for now.
Click to expand...

If you go down the V&H route, speak to your dealer and they can probably flash the ECU with a Map to suit and therefore maintaining your Warranty.

Also, if you fit slip-ons, declare it on your insurance to ensure they are covered, should you every have a spill. It's normally free as they are generally only concerened with engine mods that enhance performance greater than 5% and slip-ons will be nowhere near that.
 
Re: Tuning or not after installing slip ons?

Dazzlin said:
If you go down the V&H route, speak to your dealer and they can probably flash the ECU with a Map to suit and therefore maintaining your Warranty.

Also, if you fit slip-ons, declare it on your insurance to ensure they are covered, should you every have a spill. It's normally free as they are generally only concerened with engine mods that enhance performance greater than 5% and slip-ons will be nowhere near that.
Click to expand...
Thanks, I wasn't aware that the dealer would do that. I wasn't going to go down the dealer route as I'm sure they'll charge an arm and a leg to fit them but it might be worth enquiring.

Yeah, I'd always declare it with the insurance :encouragement:
 
Re: Tuning or not after installing slip ons?

snerkler said:
I think I'm not going to 'mess' too much whilst the bike's under warranty. I'm not bothered about performance enhancements I just want it to sound better, as long as the exhaust system doesn't completely discolour and look awful ........ In an 'ideal' world I would have it tuned to run better, but after forking out for the bike I don't have a lot of funds available, plus I'm not wanting to lose warranty hence me now deciding to put a tune on the back burner for now.
Click to expand...

I understand warranty nerves. Mine is still under warranty. It's all about having your bike run right but without compromising your ability to go back to the dealer if something happens.

At the very least, talk to your dealer first and try to buy non-Harley slip-ons through them. That can calm your fears.

But unless the dealer has a rolling road dyno, that dealer will never be able to get the bike to run right with any add-ons/upgrades.

EXAMPLE: the dealer I bought my bike from, 250 miles from home, was happy to supply V&H catless header pipes, S&S air intake and slip-ons and Dyno Jet Power Vision tune along with H-D Stage 2 torque cam. And all with no adverse effect on warranty.

"We can't offer decent Harley-brand tuning upgrades now, no issue.'' They ''tuned'' it for me pre-delivery, basically by guesswork looking at the parts and choosing one of a selection of stock PV maps.

Fast-forward 5000 miles to a nearby dealer who services my 2019 RG (until my warranty runs out, I share your caution, first time a bike of mine has been in a dealer workshop in over 20 years).

'Your bike doesn't run anywhere near as good as it should with those mods, Dave. Give it to our PowerVision-trained head tech to put on our rolling road''.

The difference after a 3hrs with the expert tuner on a rolling road? Night and day. NIGHT and DAY.

Jackpot: H-D dealership with rolling road and Dynojet PV trained staff. He adjusted all the intricate settings that the selling dealer staff did not know how to touch.

Yes it ran ''OK'' for the first 5000 miles, but I knew no better coming off a 39yr-old Shovelhead. Now it runs as it really should.

Whomp! Huge acceleration off the line and in lower gears, bags more torque, full of power, still, in 5th and 6th, blah blah. I have the dyno sheet that proves the stark difference before and after correct tuning.

Get it properly tuned as soon as you can. For the longevity of your engine. Maybe there's a dealer around you who offers what I got down here. Or bite the bullet and go to the aftermarket guy.

PS: no blue discolouration will ruin the look of your bike. When blue or straw-coloured exhausts began to offend the new age of H-D rider, the factory added cover-up ''heat shields'' to the bikes. So your ''chrome pipes'' will always appear to be unblemished chrome.

I liked the blue, myself.
 
Re: Tuning or not after installing slip ons?

kiwidave said:
I understand warranty nerves. Mine is still under warranty. It's all about having your bike run right but without compromising your ability to go back to the dealer if something happens.

At the very least, talk to your dealer first and try to buy non-Harley slip-ons through them. That can calm your fears.

But unless the dealer has a rolling road dyno, that dealer will never be able to get the bike to run right with any add-ons/upgrades.

EXAMPLE: the dealer I bought my bike from, 250 miles from home, was happy to supply V&H catless header pipes, S&S air intake and slip-ons and Dyno Jet Power Vision tune along with H-D Stage 2 torque cam. And all with no adverse effect on warranty.

"We can't offer decent Harley-brand tuning upgrades now, no issue.'' They ''tuned'' it for me pre-delivery, basically by guesswork looking at the parts and choosing one of a selection of stock PV maps.

Fast-forward 5000 miles to a nearby dealer who services my 2019 RG (until my warranty runs out, I share your caution, first time a bike of mine has been in a dealer workshop in over 20 years).

'Your bike doesn't run anywhere near as good as it should with those mods, Dave. Give it to our PowerVision-trained head tech to put on our rolling road''.

The difference after a 3hrs with the expert tuner on a rolling road? Night and day. NIGHT and DAY.

Jackpot: H-D dealership with rolling road and Dynojet PV trained staff. He adjusted all the intricate settings that the selling dealer staff did not know how to touch.

Yes it ran ''OK'' for the first 5000 miles, but I knew no better coming off a 39yr-old Shovelhead. Now it runs as it really should.

Whomp! Huge acceleration off the line and in lower gears, bags more torque, full of power, still, in 5th and 6th, blah blah. I have the dyno sheet that proves the stark difference before and after correct tuning.

Get it properly tuned as soon as you can. For the longevity of your engine. Maybe there's a dealer around you who offers what I got down here. Or bite the bullet and go to the aftermarket guy.

PS: no blue discolouration will ruin the look of your bike. When blue or straw-coloured exhausts began to offend the new age of H-D rider, the factory added cover-up ''heat shields'' to the bikes. So your ''chrome pipes'' will always appear to be unblemished chrome.

I liked the blue, myself.
Click to expand...
Thanks very much for your post. Since my last post I've actually had V&H Twin Slash installed and prior to doing so I had a long discussion with my dealership and they advised me that technically even slip ons could void warranty (other than the HD recommended Screamin Eagles) BUT obviously as a dealership they want returning custom and would not leave me high and dry if you get my gist.

As far as tuning etc is concerned I think it is something that I will look at, but at the moment I'm brassic so will have to wait. Plus, my main priority is sorting the screen buffeting and noise, over 60mph it's getting unbearable and that's wearing ear plugs, sometimes it's a pain being tall ;)

Back onto tuning etc, I don't want to start going down full systems etc as the sound level with the Twin Slash slip ons is just about right for me. Loud enough for me to hear whilst riding but not to the point the sound gets tiring, or causes people to turn and stare.
 
Re: Tuning or not after installing slip ons?

You're on the right track....the stock screen was just about the first thing I literally placed in the dealer's rubbish bin. Look at Freedom Shields.
 
Re: Tuning or not after installing slip ons?

kiwidave said:
You're on the right track....the stock screen was just about the first thing I literally placed in the dealer's rubbish bin. Look at Freedom Shields.
Click to expand...
Freedom shields and Klock Werks are the two I?m looking at, but I can?t find a U.K. stockist and shipping plus tax from the US isn?t cheap. I?m contemplating trying the MRA VSA-TYP B spoiler for now. It?ll look pants but should give me an idea whether a couple of inches extra height is going to solve it. I?ve tried all the tests of putting my hand in different positions around the tank to see if fork deflectors might help but it made no difference.

I?ve even thought about going the other way and trying a shorty screen, thinking that the main turbulence might be more chest height than head height and so reducing the noise. In terms of noise having no screen is better, but of course you feel like you?re being pushed backwards.
 
Re: Tuning or not after installing slip ons?

Toby wait and get the screen you want dont jump in and buy a product that may do the job but looks pants and you will tire of the shite look so bide your time and save for the right one
 
Re: Tuning or not after installing slip ons?

Army said:
Toby wait and get the screen you want dont jump in and buy a product that may do the job but looks pants and you will tire of the shite look so bide your time and save for the right one
Click to expand...
My thoughts are that I'd try that first to see if it helps. I'd then sell on eBay and reckon I'd lose out on ?30 tops. IMO this is better than shelling out ?250 on a screen that doesn't solve the issue. That's my current thinking anyway ;)
 
Re: Tuning or not after installing slip ons?

Bugger. I have one for a glide you could have tried , but no good for a king. Is there anyone local to you that could lend you one? Before you shell out?
 
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