Bad news and pipes and sound

OK, went to Hollister today and it was GREAT. Tore that place up, yea right. Anyway the Blue ribbon coaltion and the Hollister Hills Riding Club were both in attendance.

The topic?, quiet bikes, the tests?, free sound checks. Well I'm armed with my new Power Core 4 Q pipe. I'm good, right?, well maybe.

The spec sheet for my bike said 4500 rpm so at first they put some doohickey on my front brake resevoir and they say, "turn the throttle until I say to hold it steady." Some little wire starts to dance around and a guy with a little GPS lookin' machine is holding a rope from my pipe to the machine. They say, "NOW", and the guy says 93 db. GREAT thats three db lower than the new rule coming in 2003 and EXACTLY what FMF says/advertises.

Heres the kicker.........come back later today when the other / better sound tester is working. So I do, (free lunch x2 for the cheapskate.)

Another doohickey, now on my coil, for rpm. Gotta be more accurate than that wire and the new machine. The read? 99 - 100db. NOT GOOD. FMF says a stock yz426 is 99 and their pipe reduces it to 93. Anyway I e-mailed a note to FMF hoping for a response.

On another note for Californians, Hollister MAY start enforcing red sticker next year, read MAY. I talked to the numero uno ranger guy and got the inside scoop. He also said that starting next year sound checks will start and enforcing the 101 db for newer 4 strokes. The new land aquisition for Hollister may open next year and its mostly single track!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

And finally, if you pass a sound check in Hollister they will give you a sticker to place on your sticker (grren or red) to indicate the passing grade. That sounds kinda good but the sticker should be on the pipe not the bike...DUH

Anyway there is your update Northern Californians!


Tom, thanks for the update and information.

Something I HAVE to do, is put a TURNED DOWN tip on my Stroker SX-1 silencer. This directs the sound down and not right into the throat of their motorcycle destroyer thingy.

I will be using an automotive muffler elbow to accomplish this. It may not be pretty, but I prefer to not riding.

Tom thanks for the update, keep us posted on what FMF says. I was thinking of getting either the FMF or Big Gun It's for the pipe manufactures to get their S%&T IN GEAR!

Are you still on for Hollister next Saturday.

Stop by next week, work office is between North & South Buchanan Circles.


I have to work that day due to the maximum enforcement period. But I am surely not against going mid-week sometime after the holidays if you are game. I'm really chomping at the bit to go back to Stony.

When you do get to Hollister I would recommend riding up Donnybrook---------real gnarly....Petes path, however, was sweet.



Did they use the same dB meter the second time? Or was the only difference the tach? What about ambient noise differences? You shouldn't see that big of a difference between tests if the operator knew what he was doing. I'm assuming the bike sounded the same to your ear....


OK that last post was supposed to read NOT riding up donnybrook. DON'T DO IT!

Anyway they used their "new and better" db meter the second time and the rpm meter attached to the coil for the second test. To the layman it seemed the second test would be more accurate and then, hence, the higher reading.

They, the testers, were very good about other bikes in the area, reverberating noise, and even the fact that the bikes noise level is to be measured with the rider on it.

To say the least as every second goes by and I don't hear from FMF I'm getting rather steamed. I suppose it is possible that the test was conducted at the wrong rpm. Their wasn't a listing for the 2001 wr426 but all the "newer" bikes were 4500rpm.

Beyond that I haven't a clue.


Tom, good post! I was at middle creek last weekend and had a talk with the rangers there. They told us they were going to start sound tests in Jan.A buddy I was riding with has a white bros.pipe on his WR 426 and they thought through prevous tests on simalar bikes with said bike that it reads out at 106 db. I ride a KTM 400 with a pro circut T-4 pipe and they figured it was around 101db. Anyway I have a very active post on the KTM site on this same subject if anyone is interested. Dan :)

Just wanted to add a couple of things.

#1 - the ranger told me that they were in a hiring freeze and they needed two extra people to conduct the sound checks.

#2 - I am the #1 supporter of quiet bikes. Thats street and dirt. ie Quiet bikes save our riding privileges!!!!!



Hey gonna miss ya this weekend, but has long as you are protecting our streets and highways :) will let it slide this time. :D

Hey Tom refresh my mind (what is the Donnybrook Trail)

Have a safe and happy holiday.

Ride Safe and Ride Often :D

tom and all

the sound checks can be cheated a little.

the first trick is to be tested on grass if you can.

another one is to claim that you can't hold the bike steady at their revs but hold it a tad lower.

you can also hold onto the silencer or lift your leg and put your boot on it.

another would be to run the choke for a while as this deadens the noise.

next time your ranger man does a check baffle him with the legendary ONE-TWO. there is a false spark every other time around for the crank so does that mean that it should read 2,500revs or 5,000 revs? that may confuse him, sadly probably only for the first time.

could the above be the reason for the two DB readings.

don't give FMF a hard time, they met the DB rules as they stood. in five or ten years time we'll all be running cleverly constructed "quiet pipes" and FMF appear to have done what they said.

it's to your benifit that they have two hopelessly dissimilar readings. in the UK the judge would chuck the case out.

why don't you write to the forrestry blokes and give them the same hard time?

the least you could do is be even handed. isn't it tom?

anyway, DB readers are well known for being all over the show. they have to be recalibrated all the time.


Ahh, Donnybrook--Lower ranch-up harmony gate trail from the lodge camp second black diamond trail you run into. (after okie hill, which is closed methinks)

You will recognize her if you are riding on a drainage pipe with multiple holes in it, made from peoples footpegs.



I agree and I have know e-mailed the forestry department and the Blue ribbon coalition. I am more upset at FMF, right now, because they haven't even acknowledged my correspondence.

And, I don't believe I should have to "bend" the system to pass a sound test.

FMF clearly advertises a stock YZ426 will be reduced from 99 db to 93 db. That is their ad-not mine. I bought the pipe to be quiet...period.

If I made no improvement from the stock db why did I spend the money? Anyway again clearly the test has MULTIPLE problems and MUPLTIPLE different ways from performing and not performing will produce MULTIPLE results. That needs to be fixed.

Taffy, again, I'm not arguing and I always appreciate your knowledgable posts if I seemed to be upset only at FMF than this was my chance to say that its just not so.


Tom Maguire

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