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Discussion Starter #1
A few weeks ago I took off al thoses air filter tubes, boxes crap that come off the air box. Couldn't really see what good they did.

Anyway, I soon found out that without them the bike didn't pull so smoothly through the rev range, it would surge every couple of thousand revs and wouldn't pull past 8500 revs even in 4th.

I refitted them a couple of days ago and bingo, smooth acceleration right up to the 9500 red line in 5th and didn't get the chance to max it out in 6th but it was pulling well at 135 mph.

So just to let you all know, don't remove all that air tubing stuff, it upsets it.

My question is WHY or HOW ? Would it be the constant velocity carbs need a certain amount of resistance to create a bigger vaccum in order to lift the diaphrams ?

Pete
 

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Smart of you to figure out that the rough running would be remedied by restoring the hoses to their rightful places. :D
 

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Discussion Starter #3
Smart of you to figure out that the rough running would be remedied by restoring the hoses to their rightful places. :D
Why yes, oldndumb. I have not got to where I am in life so far by not being smart.

I have also realised that this is the second thread of mine you have replied to today, that must make you one of my biggest fans.

I'll send you a fan club membership pack, just fill in your direct debit details for the membership fee asap, thankyou.

Pete
 

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Two replies qualifies me as one of your biggest fans!?! :rolleyes:

Don't know if I want to pay for member ship in that club. Not very exclusive, is it?

Now, If you sweetened the deal, I might reconsider. :D
 

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Engine intake systems have a lot tuning designed into them. Manufactures spend a lot of time designing air box volumes, velocity stack lengths, air filter area/size and resonators. In general at lower RPM’s you will want longer overall flow paths for the intake. At higher RMP’s you will want shorter. At each RPM there is an ideal intake path length that will produce the highest volumetric efficiency (best breathing). Most engine intake systems are balance to give the best volumetric efficiency over the RPM range of the engine. The latest Yamaha engines have intake runners that are actuated to be either short or long depending on the engine RPM.

A lot of times garage mechanics like my self see all of the intake “malarkey” as simply an air restriction and eliminate it. I have made this mistake as well. This usually results in a HP gain way up at redline but large performance penalties in the mid and lower RPM ranges and effects the overall drivability of the engine.
 

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I think I would like to know why a little friendly ribbing gets people knotted?

I always find it funny when we as consumers think we know better then the engineers who spent millions developing the machines we drive....

Do we open up the hoods of our cars and go "Look at all this rubbish" and start pulling hoses off?

Some times the best lessons learned are ones that we learn for ourselves so I do appreciate posts like this and ask all weekend warriors who start pulling hoses learn from others lessons.

Cheers.
 

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A liitle bit off the question but it may help. I am reading Sportbike Performance Handbook by Kevin Cameron (MBI publishing -- I do not know if it is still in print as it was first printed in 1988). He gets right down the minute details of how to get more speed.

Flat torque curves are a result of the engineers moving the peaks around from the many parts of the engine system that help to increase torque. Changing one part may move its contribution up or down the rpm curve and its impact (increase or loss)
cam timing -- is a compromise as the valves close too late at low rpms and too early at high rpms for optimal cylinder filling at all rpms
exhaust pipe resonance -- at some rpms it adds torque and at others it will create a flat or low spot
intake system -- its length creates waves that bounce back and forth and has an rpm range where it works best and helps create a torque bump
sealed air box -- also has a resonance effect that puts its bump into the torque curve

An easy way to understand the resonance effect is the note you get when you blow across the top of a bottle. Adding water to the bottle raises the note at which the air in the bottle resonates. Unplugging the hoses to the sealed air box may drop the resonance to a point where it is no longer possible to get any resonance.
 

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I always find it funny when we as consumers think we know better then the engineers who spent millions developing the machines we drive....
I think it goes something like this.

I hear or read ...I forget
I see...and I remember
I do...and I understand
I stuff up.... I understand how and why.
 

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All else aside, this is probably a thread for the T3 forum...

Cheers,
-Kit
 

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Pete Rose???

Do you have a relative (same name) in the Colonies that played baseball and liked to gamble?? He was not too smart despite being very good at what he did for a living-maybe you are related?

have fun anyhow!!
 

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I think it goes something like this.

I hear or read ...I forget
I see...and I remember
I do...and I understand
I stuff up.... I understand how and why.
Lemansnz,
I completely agree with someone taking things apart for the sake of learning. That I can understand. :)
 

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Which is why I said it was smart of him to restore the hoses, but not the original indiscriminate yanking. :D

A phased hose yanking followed by an evaluation would have been a better plan.

Besides, all this hose yanking could be detrimental to your health.:rolleyes:
 

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I think since it's a carb'd scooter we're talking about it should go to the other forum.
 

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Where've you been, Don? Dave kicked it over to me hours ago! :D

Cheers,
-Kit
 

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Discussion Starter #16
Two replies qualifies me as one of your biggest fans!?! :rolleyes:

Don't know if I want to pay for member ship in that club. Not very exclusive, is it?

Now, If you sweetened the deal, I might reconsider. :D
If you pop over to www.sv-portal.com ( my other bikes a Suzuki SV1000s ) you'll find thousands of my fans all waiting to welcome you there...... and I'll even do you a 10% discount for cash membership.

Pete
 

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Discussion Starter #17
Do you have a relative (same name) in the Colonies that played baseball and liked to gamble?? He was not too smart despite being very good at what he did for a living-maybe you are related?

have fun anyhow!!
Not that I'm aware HiVel, and as I'm not even very good at what I do for a living I doubt it. :D

Pete
 

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Discussion Starter #18
Which is why I said it was smart of him to restore the hoses, but not the original indiscriminate yanking. :D

A phased hose yanking followed by an evaluation would have been a better plan.

Besides, all this hose yanking could be detrimental to your health.:rolleyes:
It was kinda a phased yanking, I removed all the plastic tubing, about two foot each side coming off the airbox. It comes apart in several bits but is basically a section to absord and stop water followed by a section that looks like an airbox.

I didn't touch nothing else, well except for myself but that was much later that night and a totally diferent story.

It was just an experiment ( the tubing, not touching myself you understand ) which showed that all that stuff did make a difference, albeit a bad one and so thats why I have put it all back on.

On my SV1000, we find improvements after allowing the airbox to breath easier by removing a snorkle and enlarging the intake hole.
But thats fuel injected and in conjunction with other mods and dyno tuning.

I should also add for the younger members here who maybe worried about your last comment, that I have been yanking my hose for many years without any major health effects although it can result in expensive laundry bills.

Pete
 

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If I can stop laughing long enough, I'll have to remind you that you're pushing the limits of what we allow in these forums. :D

Ahem.

Anyway... Those snorkels coming off the airbox are for much more than keeping the water out, but it sounds like you found that out the hard way.

Just an FYI, this forum is the appropriate one for your '95; the Sprint forum is actually for the later injecty bikes.

Cheers,
-Kit
 

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Discussion Starter #20
If I can stop laughing long enough, I'll have to remind you that you're pushing the limits of what we allow in these forums. :D

Ahem.

Anyway... Those snorkels coming off the airbox are for much more than keeping the water out, but it sounds like you found that out the hard way.

Just an FYI, this forum is the appropriate one for your '95; the Sprint forum is actually for the later injecty bikes.

Cheers,
-Kit
Dear Mr Kit,

Thankyou for the warning, I shall not mention air filter tubing anymore.

Also I am struggling to post in the correct forums as I'm used to the SV1000 site where there is only one model to worry about although after 5 years I still get it wrong on there at times.

While some topics are relevant to one particular model of Triumph, surely there are some things that are relevant to all models and years. General questions about tires, warrenties, biking holiday stories etc would be of interest to all. ???

It would be a shame if forum members who ride a different Triumph from me were to miss out on my incredibly funny and informative posts wouldn't it ?

Pete
 
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