Splendora, Thunder Alley pipe, and a dyno....!!!!!

Well...I have had a full and exciting weekend! I did manage to get over to Honda of Houston over the weekend. (THANKS to Josh and Glenn in the service department!) They are all super nice and efficent guys there, and the place is very MX oriented, they have a nice selection of goodies and I picked up a new 756 front tire (ahhhhhh wonderful) and a new jersey and gloves too. I think damn near every single guy in the parts and service dept. rides an MX bike!! :D I WILL be buying my next bike from them too...it is refreshing to see a dealership that does not treat dirt bikes like an afterthought...kudos to Honda of Houston!

We did run my bike on the dyno with stock and TA pipes, as well as making some major jetting changes that were rather surprising! I need some time to organize the results and scan the printouts so I can post a pic of them. Let's just say the results surprised even me, a well known Thunder Alley afficionado. I still stick by my initial "seat of the pants" review and I DO recommend this pipe if you like short shifting and massive low end boost. Example...there is a jump at Splendora where you can take the inside line and power out in second gear and still make the full stepdown, then there is a decent acceleration straightaway where you hit 4th gear for a niiiiice and fun looong stepdown. I was shifting from 2nd to 4th IN THE AIR and whacking the throttle on the landing and never had to touch the clutch, and the bike pulled like a madman. Shifting to 5th in the air then and landing for the next run at a triple was beautiful, the motor pulls the tall gear easily and was faster then revving out 4th. HINT: at 4000 rpm the TA is making SIX, yes 6hp MORE than the stock silencer. It loses a little to the stocker in the upper midrange by about 1-1.5hp though and then goes on to beat the stock on top end, but not by much. We did not have time to compare torque curves (bummer) and I will say even though the stocker had a better midrange from 5000rpm to 7000rpm, I am willing to bet the TA is making more torque than the stocker. HP is nothing without torque as we all know. The 2 size larger 175 mainjet was WAY to rich for the 94f temps and 49% humidity we had here saturday. After a moderate bottom end it hit the midrange and DIED...losses of 3-5 hp across the board from about 6800rpm on up as compared to the 168 and 170 mains. We ended up back at the stock 170 and that is what I ran at Splendora today. I tried a 168 even, and while it ran better than any other combo on top, it was suffering from massive power drops on the low end in the order of 5hp. The 170 provided the BEST low end punch of ALL the jets from 168 to 175 and was almost identical to the 168 main performance on the top end. Of course as the weather gets drier and cooler I will need to richen up but for this weekend the bike was running CRISP and started VERY easily as compared to the 175. I WILL be posting the printouts tomorrow after I scan them, and looking forward to one more dyno session with a couple of changes. I am running my air filter WITHOUT the 2-layer screen...

I also rode at Splendora with some of the HHR guys and let me tell you what, some of 'em are rather fast :) The track is awesome, very flowing with lots of 3rd and 4th gear jumps and turns. Nice sand with a clay base makes some decent berms and gas consumption goes through the roof because you can nail it everywhere!

Man, you got home fast! I'm glad you had fun and the track was in such good shape when you came...I'm just bummed I lost out on having my home track advantage on you ( :) , tell the truth, you planned it that way didn't you...LOL :D )

even though the stocker had a better midrange from 5000rpm to 7000rpm, I am willing to bet the TA is making more torque than the stocker.

Actually, HP is simply a factor of torque x rpm, so if a motor makes more hp at a given rpm it is making more torque at that rpm to produce the higher HP number.

I've got to say that I liked the bottom end on that TA, but I was also impressed with how good the stock '03 pipe is, very strong from low-mid on up. That is why the White Bros. Ramsey E-series the factory uses is so good, it has big bottom, more mid than stock and 2 more hp on top also...no weaknesses at all compared to stock. Now, if it only cost as much as a TA that would be great!

I know a lot of people will be glad to see those dyno charts, and I appreciate you bringing it down and Glenn and Josh for agreeing to run them. Welcome to team HHR!

See you next weekend! :D

mxaddict wrote:

Actually, HP is simply a factor of torque x rpm, so if a motor makes more hp at a given rpm it is making more torque at that rpm to produce the higher HP number.

Hmm....could it not be that a motor could make more torque and less horsepower at a given rpm? Say one motor makes 55hp and 30ft/lbs of torque. Another engine could make only 52hp and 33ft/lbs of torque. Just like a 150hp diesel, it is low on power compared to a Chevy 6.0 liter, but it makes GOBS more torque...and under a load the torque wins :D

But yeah, the stock system is VERY well designed, and nothing at all with running it that way. I was amazed that the stocker is so smooth and consistent, very linear on the dyno and that jives with the real world feel of the bike, very smooth and yet FASTER than stink because it is always in the powerband :D I am still very happy with this pipe for the money, and it does make mucho low end to get my heavy butt moving quickly :)

I want more dyno time! I really want to see the torque curves too, and to try some other combos...I am gonna have to work out a deal with HHR for some cheap dyno time LOL...

Hmm....could it not be that a motor could make more torque and less horsepower at a given rpm?

No, actually it can't. (quick change from mxaddict to mxgeek for a minute) Torque is the actual power being made, while HP is the amount of work that can be done in a minute(33,000 ft. lbs. a minute = 1hp)...simply put, HP is how much power x how many times the power is made in a minute(rpm). Those diesels can have huge torque numbers and a low HP because they are making that torque at very low rpms.

HP= (Torque in ft. lbs.xRPM)/5252

Torque= (HPx5252)/rpm

If you feel like doing the math you can get the torque curves using the HP and that torque formula, but it might take a while! :)

mxaddict said:

HP= (Torque in ft. lbs.xRPM)/5252

Torque= (HPx5252)/rpm

If you feel like doing the math you can get the torque curves using the HP and that torque formula, but it might take a while!


*me grabs calculator and pencil*


ahhh so they prep splendora for keith but not me... i see how it is ... oh well i went out & bashed some trees..

after a last place start i got 6th! in the 4stk C class.. & caught the 5th place guy a mile from the finish .. my chance to pass was quickly ruined by a happy throttle hand on slick hard pack...

had i not gotten held up by a xr250 in the tight woods forever ( look at lap 1 times urghh) i would have prob gotten top 3...

here are the results:( i am T27)




1 T12 DAVID LAMBERT 0:29:06 0:50:34 1:12:22

2 T98 MICHAEL ERWIN 0:28:25 0:50:39 1:12:38

3 T10 B TOMLINSON 0:29:03 0:51:39 1:14:51

4 T53 A BLUDWORTH 0:29:51 0:52:59 1:15:52

5 T85 MICHAEL SNYDER 0:29:43 0:53:27 1:17:27

6 T27 BRAD SPEARS 0:30:36 0:54:19 1:17:29

7 T69 MIKE LANGLEY 0:31:07 0:54:35 1:17:38

8 T33 PHIL WADE 0:32:37 0:57:18 1:21:56

9 T40 DON HARMAN JR 0:32:17 0:57:12 1:23:10

10 T17 JACK CLARK 0:33:18 0:58:53 1:24:01

11 T20 THAD PUTNAM 0:33:27 0:58:51 1:25:08

12 T50 GARON FOSTER 0:31:42 0:59:07 1:25:57

13 T7 S NOWAKOWSKI 0:33:09 0:59:25 1:26:02

14 T22 T22 0:34:33 1:00:40 1:26:24

15 T23 S MULFORD 0:28:18 0:51:24

16 T83 RAEL NOONAN 0:33:21 0:57:41

17 T96 CRAIG ALFORD 0:30:51 0:59:21



1 T12 DAVID LAMBERT +0:00:00 +0:00:00 +0:00:00

2 T98 MICHAEL ERWIN -0:00:41 +0:00:05 +0:00:16

3 T10 B TOMLINSON -0:00:03 +0:01:05 +0:02:29

4 T53 A BLUDWORTH +0:00:45 +0:02:25 +0:03:30

5 T85 MICHAEL SNYDER +0:00:37 +0:02:53 +0:05:05

6 T27 BRAD SPEARS +0:01:30 +0:03:45 +0:05:07

7 T69 MIKE LANGLEY +0:02:01 +0:04:01 +0:05:16

8 T33 PHIL WADE +0:03:31 +0:06:44 +0:09:34

9 T40 DON HARMAN JR +0:03:11 +0:06:38 +0:10:48

10 T17 JACK CLARK +0:04:12 +0:08:19 +0:11:39

11 T20 THAD PUTNAM +0:04:21 +0:08:17 +0:12:46

12 T50 GARON FOSTER +0:02:36 +0:08:33 +0:13:35

13 T7 S NOWAKOWSKI +0:04:03 +0:08:51 +0:13:40

14 T22 T22 +0:05:27 +0:10:06 +0:14:02

15 T23 S MULFORD -0:00:48 +0:00:50

16 T83 RAEL NOONAN +0:04:15 +0:07:07

17 T96 CRAIG ALFORD +0:01:45 +0:08:47



1 T12 DAVID LAMBERT 0:26:06 0:21:28 0:21:48

2 T98 MICHAEL ERWIN 0:25:25 0:22:14 0:21:59

3 T10 B TOMLINSON 0:26:03 0:22:36 0:23:12

4 T53 A BLUDWORTH 0:26:51 0:23:08 0:22:53

5 T85 MICHAEL SNYDER 0:26:43 0:23:44 0:24:00

6 T27 BRAD SPEARS 0:27:36 0:23:43 0:23:10

7 T69 MIKE LANGLEY 0:28:07 0:23:28 0:23:03

8 T33 PHIL WADE 0:29:37 0:24:41 0:24:38

9 T40 DON HARMAN JR 0:29:17 0:24:55 0:25:58

10 T17 JACK CLARK 0:30:18 0:25:35 0:25:08

11 T20 THAD PUTNAM 0:30:27 0:25:24 0:26:17

12 T50 GARON FOSTER 0:28:42 0:27:25 0:26:50

13 T7 S NOWAKOWSKI 0:30:09 0:26:16 0:26:37

14 T22 T22 0:31:33 0:26:07 0:25:44

15 T23 S MULFORD 0:25:18 0:23:06

16 T83 RAEL NOONAN 0:30:21 0:24:20

17 T96 CRAIG ALFORD 0:27:51 0:28:30

I'm surprised that there wasn't a torque readout given on the dyno run. As mxaddict has stated, HP is a calculated figure, not a measured one. Torque is what is measured on the dyno and then HP is calculated with that measurement and RPM.

AS for the gas/diesel power ratings, take a look at the RPM's that the ratings are taken at. The diesel doesn't turn 4500 rpms plus like the gas engine, but makes it's torque way down low in the rpm range. Just plug the numbers into the formula that mxaddict posted.

Ride on


Hey Rap, thanks for the info. You state "I tried a 168 even, and while it ran better than any other combo on top, it was suffering from massive power drops on the low end in the order of 5hp", but did you try any other pilot jets or needle clip positions? It seems that maybe the 168 main with a notch richer on the needle and maybe a 145 pilot?

No, we did not have the time to go that in depth. Another tech was waiting for the dyno, and my wife was growing impatient. :D Honda of Houston provided me with some good old fashioned hospitality :) and provided the dyno time FREE of charge. I do want to do some more testing but it will have to wait for another day...

Here is a post from last year I wrote regarding understanding the difference between HP and torque. Hope this helps:

Don't get too worked up about the difference in torque and horsepower. A horsepower is just 550 ft*lbs per second. In other words, torque times RPM equals horsepower (with the right correction constant for units). The Dyno with a horsepower versus RPM chart gives you torque. All you have to do is divide by RPM (and keep your units straight). For example, if your engine is making 35 HP at 10000 rpm, then it is generating 18.4 ft-lbs of torque. If you are making 35 HP at 5000 rpm, the engine is generating 36.8 ft-lbs of torque.

That sounds confusing but think of torque as force (it is just rotary force). Think of RPM as distance (it is rotary distance). Power is work done in an amount of time. Work is force times distance. So if you push something twice as hard, but only half as far in some amount of time, the power is the same.

Think of a "torquey" low rpm engine (like an XR) versus a high rpm 125. Imagine they are people carrying 10 pound weights up the stairs in a minute. Mr XR can carry 10 weights up the stairs at once, but he can only make one trip because he moves so slow. Mr 125 can only carry 1 weight up the stairs, but he can do it 10 times in a minute. Which is more powerful? They have both done the same amount of work in a minute, and therefore have equal power.

Why is power considered more important than torque? Because energy is conserved, and you can always regear a less torquey but more powerful engine to outpull a more torquey, less powerful one. This is pretty important to constant RPM machine tools and vehicles like boats that run at constant RPM.

In the real world though, we cant keep our bikes running at full power all the time. We need to run though the gears as we accelerate. Some people cant seem to understand how a 36 hp (peak) bike can be beaten in a drag race with a 32 HP (peak) bike. Its easy if you realize that as the bike goes through the gears, different power is generated at different RPMS, and it is the sum of the power output that wins the race. So the 36 HP engine may only be putting out more power for a small period of time during the drag race.

Also, things like throttle response are not measured for on a dyno, but it makes a difference in a race.

Well said mike! While I am intrigued and very happy that I got to dyno this pipe....it cannot account for the fact that this pipe, for me, with my riding style, is simply faster than the stocker. I certainly feel no loss in the midrange, and the increased boost and response in the bottom end and lower midrange allows me to short shift and use this motor like a 4-stroke is meant to be ridden. I have never believed in pure horsepower numbers and anyways, at our skill levels power is not the biggest factor. But you sure cannot argue with a 6hp gain at 4000rpm either...and that gets me moving with authority, right NOW :D

I guess what I am saying is, I LOVE this pipe, it DOES accelerate harder than stock, and I am happy with it. When I can drag race a 40lb lighter rider down a straight or out of a tight corner and he is riding the same bike as me and I do not lose any ground, then I KNOW my bike is running "right" and strong...and that's all that truly matters isn't it? :)

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