Thunder Alley/Just the slip-on okay??

Okay guys, I need your honest opinions. If I went with just the TA slip-on and kept my titanium header for my 450F, do you think it would be worthwhile, or would I be missing the boat? I thought that I heard somewhere that with just the slip-on that there would be a substantial performance gain. I appreciate your taking the time to give me your thoughts!

I had a TA pipe on my 426 with the stock head pipe and saw a big difference over the e-series silencer and high boy head pipe.Give bob a call he is a nice guy and will help you out.If he says the 426 pipe will fit the 450 i'll sell you mine i am happy with the stocker and i'm not going to use the TA anymore.I bought it a couple months ago.

Later :)

Thanks, do you recall what Bob charges for just the slip-on, I think the web-site said $350.00 for the both the header and muffler.

It is 250 for the slip-on and 295 with the SA.

i tried the DR. D slip on only...and it made a big big improvment on my 450.. Doug told me that he could not really improve on the stock yes.. just the slip on is all you need..

How much do you want for the TA Blue One? Is it coated? Let me know at thanks



Call Bob at Thunder Alley and order one. The slip-on costs $250 - Bob sends it to you with an invoice - if you don't like it, send it back - if you do like it, send him the check. Bob is a great guy to deal with, he is very knowledgeable and stands behind his product. Come-on - imagine FMF saying "Try it out and send us a check if you like it" - yeah right!

I usually don't respond to questions asking "what's better for my bike" - mainly bacause that's a matter of personal preference. What works for me doesn't mean it'll work for you. But anytime someone asks about the T/A exhaust, I immediately respond. That's how strongly I feel about this product. I installed one on my 00'426, and I honestly feel that there isn't a better choice. Friends ride my bike and are blown away at the Gruntier feel - this thing rips.

That said - I am no longer responding to T/A questions. I'm starting to sound like a salesman. Bob - if you're reading - send me some stickers. :)



I know how you feel Odie. I love my TA pipe as well, it definitely makes the low end come alive in a rip-snort-fire-breathing type of hit. My bike had a 6hp gain at 4000rpm....

Don't take the dyno too seriously though, it is a tool, only that, and dyno runs don't accurately reflect the real world conditions a motor operates in, such as throttle response, traction levels, riding styles. etc. I initially was expecting to see some bigger numbers in the midrange, but hey, once I got on track and the thing is just plain faster than the stocker, I forgot about the dyno and just rode the damn thing and had a BLAST...

I too am accused of sounding like a TA saleman hehe...I need a couple of new stickers too :)

On a side note, I do not think I have EVER read any stories from a rider that actually installed a TA pipe and did not like it. I have see PLENTY of people thought that doubt it, but they have never even RIDDEN the bike with a TA pipe on it...ya gotta try it to know. :D

i have ridding Raps bike & his 450 with the thunder alley does run well ... how well .... about as well as a modified kx100 with a 110 kit... :D haha Actually its pretty peppy .. I rode it the other day & was pretty impressed... not to mention it sounds pretty unique on the track...

I give it a rating of :

Looks: :D:D

sound: :D :D ;)

Performance: :D:):D :D :D :D


How do I get hold of Bob does he have a web site or email address

You can check out Thunder Alley at:

All of the information you need should be there.

BTW the pipe is just awesome, It pulls sooooo hard in the bottom end, third gear feels like second gear coming out of corners. The sound of the pipe is awesome also, it has a really deep "thump...thump" sound. I tried the spark arrestor and the standard core and to me the standard core sounds way better and performs better also. It is hard to tell though cuz I rode both on different tracks. Later..

dmxracing said:

BTW the pipe is just awesome, It pulls sooooo hard in the bottom end, third gear feels like second gear coming out of corners. The sound of the pipe is awesome also, it has a really deep "thump...thump" sound


I'll agree there, it lets you pull third out of even fairly tight "square off" type I said I can shift from a second gear seat hop jump to 4th in the air, and land with gas on and it clutching, no more shifting down a long stright to the next jump, it just PUUUUULLLLLLLLLLS long and hard....much harder than stock.

Can you tell I am satisfied :D

and oh yeah Loopout....the kx100 comment was just plain mean :):D :D that's it, the DRAG RACES ARE ON NEXT TIME AT THE TRACK. Bring your slicks!!!

Thanks guy's for you all taking the time to give me your opinions!!

I just spent 45 enjoyable minutes on the phone with Bob Murray and ordered a system from him.

I was very impressed with his knowledge and candor and his committment to making exhaust systems the way they should be hand! I am very excited, to say the least, about the arrival of the pipe.

I told Bob that up here in Montana we also subscribe to the theory of doing/making things by hand since a lot of us are farmers/ranchers and sometimes to get things done right, you have to do them yourself.

I told Bob that I have a feeling that he will be getting a lot of calls from Montana since this is the first of his pipes to be here. I will certainly give it a lot of exposure!

Again, thanks so much for all of your help, I consider this board my BIBLE for thumper information :)

Thunder Alley pipes are seeming to grow in popularity...some people are afraid of trying a relatively unknown product, but with all of the exposure Bob is getting now I think some people are loosening up and giving him a chance. Like I said I have never heard of a guy that bought a TA pipe and did NOT like does what Bob says it does, plain and simple, and that in itself is something you can't always count on in today's world. Not to mention they are strong and well built. And "factory" looking with the bare metal :), rust has NOT been a problem as long as you squirt some WD40 or something like that on it after washing.

just back in from burning my 739 into a slick.... bring it on rap... bring it on man hahhhaa

I'll meet ya at the palace bingo at 11pm.. & i will even disconnect my sneake pete Nos system...

off to install wheelie bars ... :):D

I just ordered my slip on from Bob and he told me that the stock 03-450 head pipe was fine and made from titanium, so no advantage to changing the head pipe.

I've had mine for about two weeks now and there is definately a change in low end performance with this pipe. I was pretty good on my jetting before changing to this pipe. Anyone know what kinda changes, if any, changing the main jet up one size will do?

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