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Discussion Starter #1
Just got my bike off the dyno & have lost 18hp!
3 weeks ago with an SE pipe, stage 1 download & topless she pulled 110.2 & 76.7ft/lbs. We then fitted a 240 wheel kit, BUB cone exhaust & a PC111 expecting to gain another 3 to 5 hp.

What we got was 92.2hp & 70.2ft/lbs!!!

We spent hours running the bike on a dynojet rig, the guy with the rig is a much respected road race tuner & dynojet agent & I have been an amatuer tuner & bike builder for 30 years. So you can assume we tried every configuration of the obvious; belt tension, tyre pressure, suspension etc.

No luck, we called dynojet who told us that they had seen large power losses with wide tyres due to tyre construction & contact area with the roller.

I find this hard to believe, but have no other explanation. The bike runs really sweet & I've just hammered it up my favourite hill & it feels really powerfull.

So if anyone has any valid opinion on the width & construction of the tyre causing such a problem, please let me know.

If it is true, does anyone want to buy a wide wheel kit!

Paul.
 

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african paul said:
Just got my bike off the dyno & have lost 18hp!
3 weeks ago with an SE pipe, stage 1 download & topless she pulled 110.2 & 76.7ft/lbs. We then fitted a 240 wheel kit, BUB cone exhaust & a PC111 expecting to gain another 3 to 5 hp.

What we got was 92.2hp & 70.2ft/lbs!!!

We spent hours running the bike on a dynojet rig, the guy with the rig is a much respected road race tuner & dynojet agent & I have been an amatuer tuner & bike builder for 30 years. So you can assume we tried every configuration of the obvious; belt tension, tyre pressure, suspension etc.

No luck, we called dynojet who told us that they had seen large power losses with wide tyres due to tyre construction & contact area with the roller.

I find this hard to believe, but have no other explanation. The bike runs really sweet & I've just hammered it up my favourite hill & it feels really powerfull.

So if anyone has any valid opinion on the width & construction of the tyre causing such a problem, please let me know.

If it is true, does anyone want to buy a wide wheel kit!

Paul.

It's the Bubs bub! That is the standard result with Bubs or Sampson's. They are huge power robbers.


John
 

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Color me Gone
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Paul I would like to tell you it's your wide wheel kit and buy it cheap but what John says is typical of the Bub pipe.

Max
 

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Was it on the exact same dyno ?
Different dyno produce different results!
Even the same type dyno in different locations.
Even different users can vary output.(some) :soapbox:
BobT
 

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FASTESTSTKBLTDRV
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We Tune A Lot Of Drag Bikes With 25 Inch Tires
On The Dyno Jet 250 With Out Any Problems
Other Than To Much Power At Once Smokes
Them. It Is Not Your Wide Tire Kit!
 

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Discussion Starter #6
BUB pipes are rare over here so they have no reputation, I did have to panel beat the damn thing to get it to fit though!
Are these pipes a well known piece of crap over there? On the face of it, in comparison to the SE pipe it looks like it would breathe freely, even though the BUB pipes are a different lengths.
Suppose I'd better put the SE back on, disconnect the PC & see what it reads. I hope you guy's are right 'cos the wheels sure look sweet.
Thanks,
Paul.
 

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Discussion Starter #7
Rick Nielson said:
We Tune A Lot Of Drag Bikes With 25 Inch Tires
On The Dyno Jet 250 With Out Any Problems
Other Than To Much Power At Once Smokes
Them. It Is Not Your Wide Tire Kit!
Thanks Rick, that gives me confidence, I'll try the SE again.
Paul.
 

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african paul said:
BUB pipes are rare over here so they have no reputation, I did have to panel beat the damn thing to get it to fit though!
Are these pipes a well known piece of crap over there? On the face of it, in comparison to the SE pipe it looks like it would breathe freely, even though the BUB pipes are a different lengths.
Suppose I'd better put the SE back on, disconnect the PC & see what it reads. I hope you guy's are right 'cos the wheels sure look sweet.
Thanks,
Paul.
Paul, it's the pipes, no doubt about it! And yes they have a deserved reputation for being crap. You can still use the PCIIIr as there is a map for your set-up, plus some dyno time can squeeze out a couple of extra ponies.


John
 

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It's probably the bubs but the wheel/tire package can also rob HP if the combination weighs more than the stock setup. You're measuring rear wheel hp using an inertial dyno. It measures the amount of energy needed to accelerate a known mass, the roller. If you add more mass to the package then the engine has to accelerate the wheel/tire combo in addition to the roller. It isn't going to give you an 18 hp loss, more likely 2 or 3 hp. The again, if you have forged wheels then the combination of the lighter wheel and the heavier tire should cancel out.

Put the SE's back on, remove the PCIII and take a baseline to see exactly how much power the 250 is robbing. That will tell you what the Bubs did. When you're dealing with unknown upgrades you need to change one thing at a time, but you knew that ;)

BTW, it's the Bubs, they're crap :yak:
 

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Discussion Starter #11
Thanks for all the input guy's, I think you are right, only the pipe could make this much difference. I'm gonna put the SE back on in the morning & see what the output is.
If it is the BUB am I allowed to lynch them, horse theft is a hanging offence over there isn't it?
I will report back.
Paul.
 

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Only in Texas... :laugh:


african paul said:
Thanks for all the input guy's, I think you are right, only the pipe could make this much difference. I'm gonna put the SE back on in the morning & see what the output is.
If it is the BUB am I allowed to lynch them, horse theft is a hanging offence over there isn't it?
I will report back.
Paul.
 

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Discussion Starter #13
Excellent, will George W do it personally & can I watch?
Took her out on the freeway last night & nailed it, she goes flat at about 7 grand where previously I used to get shot from a cannon when she came on cam.
Slept on it & decided what to do, gonna refit the SE just to check & then we will make a pipe that works.
I have some shots of Kaz's bike, does anyone else have any pics of pipes that work so I can get an idea of a starting point for length & diameter?
Also whats the message on 2 into 1 as opposed to twin pipes?
If you can help my mail address is [email protected]
Thanx all,
Paul.
 

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Paul,
Relax my Friend!
I have made 190+ with my Rick's 240 Setup on. So No !It's those Sorry A$$ Pipes! :chair: Try any of the Top 3 2 into 1 Pipes- 1st.TT, 2nd.ST, 3rd.JM.If Your Tuner is as Good as you say get a HD Race Tuner and really TUNE Your Bike! :thumb:
 

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Can you flame the Bubs? Hell yeah!
Can I help? Plis? Huh?

Kaz we here in the tropics may be trying the JM vs ST on a same dyno, both stock bikes. I'll offer him some $$ just to have him dyno mine then put the ST on mine then dyno again, see what happens, if diff of 1hp either way I'll keep the JM for looks but if much more diff on my disadvantage I'll switch. Guy still needs some convincing. I don't get it they're just POS metal pieces you put on and take off see what happens. So possesive about material $hit. We could do it the other way around I don't care. Just a fricking motorcycle. What I know for sure is I'm really sorry for african paul's results.

So Bubs for V-Rod :chair: :spank: and :alien: you! :broke: An 18hp loss is just insane. Is that really typical? I mean the huge amount lost.
 

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While they work good on the traditional V-Twins such as the Evolution motors and the Twin Cam's, the Bub's, from all I have read (I am in the market for a VRSCA...leaving to check out a new 03 for $15,300 US in a minute) they are hindering V-Rod performance. i heard that they sound great, and in my opinion look sweet too, but they are killing the performance. I think H-D and Porsche already did a nice job on the motor to get the numbes they get stock so maybe some real hard earned $$$ aside from the usual Harley-Tax (Air cleaner/pipes/download), is the only real way to gain some HP.

I personally cannot afford to dyno every other week so personally, I will likely go with a similar setup to your original with the 16ga SE's, prolly the race tuner (maybe that or the SE stage 1 download), and a lid mod like Ketsugo uses. When i get my V-Rod, it will be my daily rider, my chopper, and my tourer all in one since my income only allows for one bike at a time.

Later,
Gary

PS

It's amazing how popular this bike is over sea's and the luke warm "general Harley Crowd" reaction to this bike. I think it is the coolest looking and most attractive bike any manufacturer has made in a long time! It's the bike I wish they made 5 yrs ago when I got my old Sportster. Then again, wherever I have seen the V-rod parked, even next to the choppers, the VROD seems to get equal or more time from passers by. Just a sweet bike all around...stock or heavily customized.
 

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Discussion Starter #17
Hello my colonial buddies,
Guess what, re-fitted the SE this morning, stuck it on the roller & hey presto! all my power back!
The exact drop was from 110.2 to 92.2!!!
When I was looking to buy the BUB they were all over me like a rash, when it didn't fit & I e-mailed them for advice they totally ignored me. Now I find that their pipe is the peice of crap it looked to be when I took it out of the box, I could weld better with a zippo!
'Every ounce of power the vrod can deliver' their ad says, my arse!!!

Now I'm gonna send them the dyno print outs & demand my money back, it aint right taking advantage of a poor deluded limey.

I am a bulldog & they will feel my bite!

Feel much better now.

Please tell me what TT, ST & JM stand for.

Thanks for listening,

Paul.
 
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