Triumphrat

Sactown Speedy · 06-17-2012, 03:44 PM

I have read alot of comments. / conjecture regarding performance damage / decrease with the Corbin seats based on air intake / seat pan design so my question is, is there any proof to the claims? I find it hard to believe that in this litigious world that Corbin could sell a product that could damage the machine it was designed for.

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dazco · 06-17-2012, 05:35 PM

Quote:

I find it hard to believe that in this litigious world that Corbin could sell a product that could damage the machine it was designed for.

I consider my experience proof. Not that i had a corbin but this relates directly to it. As to damage tho, i can't see that. But huge loss of performance IS very possible. I removed the duct under the seat to increase the air intake area thinking it might be a performance enhancement. Had to remove the seat covering to remove it because it not only has screws holding it on you can see, but also has some that screw into it from the reverse side under the seat cover and foam. Anyways, i ran with and without it over the course of a few months and what led me to put it back permanently was that i saw someone mention that it's a tuned duct and it hurts the bikes low/mid range. At that point I'd been running it since i have the 1700 kit installed and I put it back and sure enough a considerable boost in power over running w/o it. So it stands to reason that if a LARGER airway caused such a loss, then it is indeed a tuned port and whether you increase it, decrease it, or just change the shape of the air's pathway under the seat you're going to loose power. I have mentioned it to potential corbin buyers several times after noting that corbin does NOT retain the ducting. Corbin from what i've seen is not very customer friendly nor do they seem to care about things like that as long as theres cash involved. If you have to have a different seat my advice would be have the stock seat redone with whatever cushion and covering material you want that suits your needs. Personally if i were to do that corbin would be one of the last places i'd take it judging by all the horror stories i've read about them.

Lantesh · 06-17-2012, 08:59 PM

When I had my seat custom modified I told the guy I wanted it done on the stock seat pan. I figured that ducting was there for a reason. It is nice to see I was correct.

dazco · 06-17-2012, 09:17 PM

Smart man, ya done good. It's common sense that without actually trying it there should be a question in your mind about it. Thats why i'm down on corbin. I can't imagine any company like that looking at the stock seat, seeing that duct and not taking that into consideration. Seems extremely incompetent to me. But then it just goes along with everything else i've read about them.

Lee H · 06-17-2012, 09:44 PM

Corbin is just like any other company. They will sell what the public will buy. It is common for companies to sell mods that decrease performance. Half the intake and exhaust kits I sell/install are inefficient designs, but people keep buying them.
Unlike many other seat companies, corbin offers the option of building a one off seat to the rider's specifications. They will even measure you and your bike, and make a full pan and seat just for your bike. This option is expensive, but worth it if you put enough miles on the bike

as to the "tuned" intake breather. The intakes/throttle bodies on the engine are too large for proper intake velocity. The two most common ways to increase intake velocity are smaller diameter intake plenums, or longer breathers. Triumph chose a longer breather. IF you chose to remove this, you have to decrease the air inlet diameter, and create a venturi effect to regain the velocity. In truth, the design flaw was the motor company's, not the seat manufacturer, but blame is easy to displace.
Anyway, any competent mechanic should be able to figure out how to add a venturi to the air box after a snorkel is removed

DocT · 06-20-2012, 02:42 PM

Quote:

Originally Posted by Lee H

Corbin is just like any other company. They will sell what the public will buy. It is common for companies to sell mods that decrease performance. Half the intake and exhaust kits I sell/install are inefficient designs, but people keep buying them.
Unlike many other seat companies, corbin offers the option of building a one off seat to the rider's specifications. They will even measure you and your bike, and make a full pan and seat just for your bike. This option is expensive, but worth it if you put enough miles on the bike

as to the "tuned" intake breather. The intakes/throttle bodies on the engine are too large for proper intake velocity. The two most common ways to increase intake velocity are smaller diameter intake plenums, or longer breathers. Triumph chose a longer breather. IF you chose to remove this, you have to decrease the air inlet diameter, and create a venturi effect to regain the velocity. In truth, the design flaw was the motor company's, not the seat manufacturer, but blame is easy to displace.
Anyway, any competent mechanic should be able to figure out how to add a venturi to the air box after a snorkel is removed

I'm far from being a engineer...but it seems to me that the design was made to work very well by Triumph...If the seat maker wants to have the correct outflow, it needs to design the seat to better match that of Triumph's. Whatever the accessory you're adding needs to keep the manufacturer design of the vehicle/bike/whatever in mind otherwise a compromise in power would occur...so with that in mind, the accessory company (Corbin in this model) would be the designer flaw...

I probably made that about as clear as mud...

dazco · 06-20-2012, 03:20 PM

Quote:

Originally Posted by DocT

I'm far from being a engineer...but it seems to me that the design was made to work very well by Triumph...If the seat maker wants to have the correct outflow, it needs to design the seat to better match that of Triumph's. Whatever the accessory you're adding needs to keep the manufacturer design of the vehicle/bike/whatever in mind otherwise a compromise in power would occur...so with that in mind, the accessory company (Corbin in this model) would be the designer flaw...

+1 .........................

Daycruiser · 06-20-2012, 05:33 PM

My very custom Russell Day Long seat is built ground up on the stock pan. No issues with intake.