ATT and exhaust questions...

[Toovalks]

I'm sure I had you guys wondering??? But it really is 2 questions.
Has anyone here tried the Delkevic exhaust for  the Valkyrie???  Easy one ??? Thoughts on the Delkevic exhaust???
Second Question, I bought an ATT in 2017...  Manufacture date...29th week(late July) 2016 , I'm ready to put it on buttttt it is really close to 4 yrs. old.... been stored inside my shop, on it's side.on top of another tire.. under a work bench.....no uv...probably very little O3  but below 32 degrees on occasion.... Should I do it???

[Skinhead]

Why not?  Check the load rating on the ATT, I'm sure you're no where close to it on the Valk.  That means extra safety factor.  The 6 year thing is a guide line.  Tires don't just explode 6 years from the manufacture date.  But do what ever makes you feel safe.

[da prez]

I would use it. I am sure others will hang me. Get some tire treatment.  I used it on my street rod
 

          da prez

[h13man]

I'd use it. Extreme heat and sunlight are more contributing factors to deterioration and it wasn't mounted. Go for it. If you don't want it I be glad to buy it from you.

[98valk]

I contacted ebay seller about Delkevic  a few yrs ago.  they stated header pipe has slightly larger inside diameter vs OEM. That will give some extra HP and torque through out the rpm range.

[Toovalks]

 Thanks for all the support... I haven't decided yet about the tire... but soon, I don't ride enough to really do it justice  sooo ...maybe I will let you "have" it.,
One of my concerns about  the Delkevics are that the headers are not double wall and I worry that they would be turning blue in a hurry. Maybe if they are larger Diameter that would drop the exit temperature???

[MarkT]

I contacted ebay seller about Delkevic  a few yrs ago.  they stated header pipe has slightly larger inside diameter vs OEM. That will give some extra HP and torque through out the rpm range.

It might provide more HP at high rpm, especially if you have other performance mods like a blower and head porting that match the headers - otherwise, not so much.  The OEM headers are matched to the engine as a tuned system.  More torque?  No.  It will be less than OEM headers with glasspacks.  Smaller headers have higher velocity which increases torque.  Known fact.  The Honda engineers knew what they were doing.  Don't take my word for it.  There's been lots of dialog even here on this issue.  Or google it out there on the interweb.  Or ask Bob Smith / any other performance experts.

[98valk]

I contacted ebay seller about Delkevic  a few yrs ago.  they stated header pipe has slightly larger inside diameter vs OEM. That will give some extra HP and torque through out the rpm range.

It might provide more HP at high rpm, especially if you have other performance mods like a blower and head porting that match the headers - otherwise, not so much.  The OEM headers are matched to the engine as a tuned system.  More torque?  No.  It will be less than OEM headers with glasspacks.  Smaller headers have higher velocity which increases torque.  Known fact.  The Honda engineers knew what they were doing.  Don't take my word for it.  There's been lots of dialog even here on this issue.  Or google it out there on the interweb.  Or ask Bob Smith / any other performance experts.

Again you are wrong. I've done dyno work on my bike and along with the Viking original dyno which I posted to u before the OEM pipes are undersized and are choking the engine. Done that way for EPA testing and Honda warranty.  I did marine industrial piping design for many years. having pipe too small increases velocity but the volume goes down. there was always a balance. the OEM pipes are too small making the engine work harder and thereby reducing MPG and power.

[MarkT]

"Again I am wrong"?  

I was educated as a scientist to make supportable statements. However your exhaust brand and their  patron made performance claims that were not believed by others who built Valkyrie exhausts and so I believe their dyno data was embellished.  I recall wild claims from back then, and others refuting them.  Though such comments were minimized here on the VRCC venue as the unbelievers didn't want to be banned by the board operator - who now is no longer involved and the company went out of business.  I saved some of that dialog.  Now I am just about the only exhaust builder left - most all have left as 1500 Valkyrie suppliers; some died.  Meanwhile your mentioned result on ONE Valkyrie is statistically meaningless.  So many variables including how was the dyno setup and used.  What else was involved with your engine.  The known published results of comparing only header diameter size changes across all venues and many tests bears out my statement.  Without other variables, changing only the header cross section, a well matched cross section as designed by Honda engineers, a somewhat smaller diameter than the ones bigger than the header ports, increases velocity and as a result, streetable torque with it.  Other changes from the OEM exhaust improve power - mainly replacing the constricting muffler mandated by the govt with a full-flow one, and changing the config to 3-1 to add scavenging, both noticably increase power.  If the Delkevic system has those design factors, they will also improve power over designs like the stock exhaust.  But larger headers, bigger than the head ports do not create a torque increase for an otherwise unmodified engine.  There is a trade-off - at very high rpms there may be slightly more hp with larger headers - if the flow isn't already restricted by the head's port size.  Do you race your Valkyrie?  More torque, evenly distributed across the rpm band, makes your cruiser more streetable.

No I am not wrong.  Google this; check the results among many engine experts.  

There's another trade-off.  Do you want to have colored headers (and in the case of Cobras, corroded / perforated) if you think larger headers are better?  Honda headers won't color if you don't abuse them by overheating.  Cobras are known to perforate after a lot of miles - which our bikes will last for.  Don't know about Delkovic longevity; they haven't been extant for a long time; don't know the wall thickness of their headers or the grade steel.

Go ahead and have the last word - I'm done with this.  Couldn't leave your partially wrong statement unrefuted for public consumption.  I know, and so do my customers, of the increased power put out by my exhaust mods over stock and other designs that don't have 3-1, high flow muffler, similar diameter headers.  I believe designs like Delkovic's are an improvement but are not optimal with larger headers.  Mic drop.

[Savage]

"Again I am wrong"?  

I was educated as a scientist to make supportable statements. However your exhaust brand and their  patron made performance claims that were not believed by others who built Valkyrie exhausts and so I believe their dyno data was embellished.  I recall wild claims from back then, and others refuting them.  Though such comments were minimized here on the VRCC venue as the unbelievers didn't want to be banned by the board operator - who now is no longer involved and the company went out of business.  I saved some of that dialog.  Now I am just about the only exhaust builder left - most all have left as 1500 Valkyrie suppliers; some died.  Meanwhile your mentioned result on ONE Valkyrie is statistically meaningless.  So many variables including how was the dyno setup and used.  What else was involved with your engine.  The known published results of comparing only header diameter size changes across all venues and many tests bears out my statement.  Without other variables, changing only the header cross section, a well matched cross section as designed by Honda engineers, a somewhat smaller diameter than the ones bigger than the header ports, increases velocity and as a result, streetable torque with it.  Other changes from the OEM exhaust improve power - mainly replacing the constricting muffler mandated by the govt with a full-flow one, and changing the config to 3-1 to add scavenging, both noticably increase power.  If the Delkevic system has those design factors, they will also improve power over designs like the stock exhaust.  But larger headers, bigger than the head ports do not create a torque increase for an otherwise unmodified engine.  There is a trade-off - at very high rpms there may be slightly more hp with larger headers - if the flow isn't already restricted by the head's port size.  Do you race your Valkyrie?  More torque, evenly distributed across the rpm band, makes your cruiser more streetable.

No I am not wrong.  Google this; check the results among many engine experts.  

There's another trade-off.  Do you want to have colored headers (and in the case of Cobras, corroded / perforated) if you think larger headers are better?  Honda headers won't color if you don't abuse them by overheating.  Cobras are known to perforate after a lot of miles - which our bikes will last for.  Don't know about Delkovic longevity; they haven't been extant for a long time; don't know the wall thickness of their headers or the grade steel.

Go ahead and have the last word - I'm done with this.  Couldn't leave your partially wrong statement unrefuted for public consumption.  I know, and so do my customers, of the increased power put out by my exhaust mods over stock and other designs that don't have 3-1, high flow muffler, similar diameter headers.  I believe designs like Delkovic's are an improvement but are not optimal with larger headers.  Mic drop.

 

[Toovalks]

wow...sorry!!!