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Discussion Starter · #1 ·
I could've sworn that this has already been covered, but my search came up empty, so here goes:

Has anyone else noticed how the K&N replacement air filter for the 1050 is a poor fit? It doesn't seal properly around the airbox; in fact, there's a noticeable gap! I thought it might just be me, but when getting my 24K service, the shop's tech and owner made the same observation. If anyone else shares this experience, what did you do? I'm concerned that the gap may allow unfiltered air to enter the airbox (path of least resistance) and let crud into the engine. Also, that it may throw off the critical air/fuel balance needed for clean response. I've recently encountered an occasional hesitation when cracking the throttle open while in 4th/5th/6th gear, @ +/- 3-4K rpm: it won't catch, and the only remedy is to back off and reapply throttle at a more gradual rate. This was previously never a problem, so I'm a little stumped: filter is clean, plugs are clean, no vacuum in the tank (ie. pinched vent hose), everything seems OK. Any similar experiences/feedback would be gratefully appreciated...

Thanks!
 

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Yeah, there are a bunch of complaints on this. I don't know why you couldn't find the threads though.
Mine fits tight, but doesn't have a gap like others claim. The plastic on the filter seems too hard. I'd think it would fit better if it was softer and more flexible.
 

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Somebody else here documented the same problem, so you are not alone. Don't recall the member though! :mad: I'm sure you did, but I think your supposed to use the OEM gasket. The gasket was NOT the problem the other member had with his fit though. It was molded improperly. I think he got a replacement from K&N, and if I remember, it wasn't any better. Personally, I just did the simple "OND free air" mod!:D
 

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I had a problem with a K&N filter.

Used the gasket off the stock one, set it place and as I pressed the top of the airbox down to get everything sealed up & locked together, you could watch it bend the airbox out.

So I dug out my dremmel and shaved the edges of the filters frame, but no amount of "modifying" would let it sit in its recess, be able to place the lid in its exact spot and not bend the lid.

After wasting the day doing that, I took it back and got a new factory one. Didn't do the OND mod. to it but probably will with the next one at hte next service.
 

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Just stay stock I think the oem filter is fine...as the gains with the K&N in my opinion are not worth it. just my 2 cents worth
 

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Coincidentally, I thought that I had lost the calculations for the filter mod and happened to find them last week.

These are rough msmnts.

Filter surface area: 38.31"sq
Total area of holes in stock filter flame arrester: 18.89"sq
Obstructed area of stock filter w/arrester: 19.43"sq

Arrester removal increases unobstructed filter area by 50 per cent.
This efficiency gain comes without sacrificing particle filtration effectiveness.

You can do it and still keep the K&N stickers on the bike. No one will know. ;)
 

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Discussion Starter · #8 ·

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Discussion Starter · #9 ·
Stealth

Coincidentally, I thought that I had lost the calculations for the filter mod and happened to find them last week.


This efficiency gain comes without sacrificing particle filtration effectiveness.

You can do it and still keep the K&N stickers on the bike. No one will know. ;)
Ha! I like your line about the stickers! No, I didn't put any on my bike: those are for race cars, bikes, etc. Paying sponsors. Maybe if K&N gives me (for free) a filter that fits, I'll consider marring the Sprint's beauty, and put their sticker on the underside of the bellyban... I like your solution and will look into it (I hadn't seen it before), though the actual reason for the K&N was primarily cost-saving; the performance aspect was to be a fortuitous benefit. Thanks for the heads up!
 

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Just stay stock I think the oem filter is fine...as the gains with the K&N in my opinion are not worth it. just my 2 cents worth

Have you used one ricster to compare and make this statement?

I run one on my Sprint ST although I know and beleive they would let more crap in than stock but it does deliver a surprisingly more crisp throttle response than with the standard filter when used in conjunction with the Triumph off road can and correct tune.

That is a fact, it may not give more power but the delivery is more crisp and quicker to respond to the throttle opening.

DaveM:cool:
 

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Dave, you failed to say how many K&N stickers are on yer bike. Those are wot makes it go fast. :p
 

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Have you used one ricster to compare and make this statement?
Dave

You are a doubting Thomas aren't you?:D

I'll back up Ricsters comment with some evidence.

We dyno'd a bunch of Sprint and S3 1050s just before Christmas on the same dyno at Triumph Melbourne. Some of the 1050s were running BMCs and K&Ns.



The bike that produced the most torque through the range and maximum horsepower had a dirty old stock air filter that was due for replacement after 20,000km of use. The guys who ran the dyno said an aftermarket K&N filter will not provide anymore horsepower than a stock filter so don't waste your money!

Having seen how much crap a BMC filter let through on my mates 1050 there is no way in the world I would put one of those or a K&N on my Sprint.:eek:

If you want flow and good filtration it is hard to go past ONDs mod to the stock filter.;)
 

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Ralphus

Nope but if you read my post I was not refering to hp I have seen this table you just posted before and already knew that anyway.

Read my post again.

Last time we had a little episode it was not me that was doubting:D

DaveM:cool:
 

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Use BMC Air Filters

I could've sworn that this has already been covered, but my search came up empty, so here goes:

Has anyone else noticed how the K&N replacement air filter for the 1050 is a poor fit? It doesn't seal properly around the airbox; in fact, there's a noticeable gap! I thought it might just be me, but when getting my 24K service, the shop's tech and owner made the same observation. If anyone else shares this experience, what did you do? I'm concerned that the gap may allow unfiltered air to enter the airbox (path of least resistance) and let crud into the engine. Also, that it may throw off the critical air/fuel balance needed for clean response. I've recently encountered an occasional hesitation when cracking the throttle open while in 4th/5th/6th gear, @ +/- 3-4K rpm: it won't catch, and the only remedy is to back off and reapply throttle at a more gradual rate. This was previously never a problem, so I'm a little stumped: filter is clean, plugs are clean, no vacuum in the tank (ie. pinched vent hose), everything seems OK. Any similar experiences/feedback would be gratefully appreciated...

Thanks!
My Triumph dealer uses BMC Air filters because of issues with the K&N filters on the Sprint ST 1050.
Keith
 

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Unfortunately, K&N doesn't make any distinctions re HP gains for the stickers. I think it is because of the various sizes.

But, since you have the two bikes (unlike we poor blokes) you could consider moving the sticker from bike to bike and see what the difference is. Please do it one sticker at a time for safety's sake. :D
 

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Have you used one ricster to compare and make this statement?

I run one on my Sprint ST although I know and beleive they would let more crap in than stock but it does deliver a surprisingly more crisp throttle response than with the standard throttle when used in conjunction with the Triumph off road can and correct tune.

That is a fact, it may not give more power but the delivery is more crisp and quicker to respond to the throttle opening.

DaveM:cool:
If you feel it does DaveM that is great....my feeling is the amount of dirt it lets in (read silt) its not worth it to me. I have alot of experience with race motors with cars and I feel a motor is a motor and we did dyno runs on the porsche motors we used to build and it made if I remember correctly like 1hp at redline.....if you want more power..the old addage is..."no replacement for displacement" not micky mouse things like airfilter and fuel additives and other hokus pokus cures. And thats not a stab at you DaveM its just that I deal with this stuff all the time at the dealership.
 

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Discussion Starter · #18 ·
Yikes!

I didn't mean to launch a pro/anti-K&N debate (good-natured and tongue-in-cheek though it is!); believe me, I had no real convictions about their filter one way or the other, though I now don't think much of their QC, raising more questions about their product development and execution in general. I've never bought into the concept of K&N adding instant 10% HP increase: that's for those who think the "Cyclone" will turn your Taurus into a McLaren! Given the trade-off between airflow and engine protection, I'll opt for protection any day of the week, though I figured that given K&N's dominant position within the air filter aftermarket, it's (protective) performance would be adequate. Also, if a small HP gain were realized, then so much the better: I hoped that the increased air-flow (along with the richer TOR tune), would better serve the less restrictive Trident exhaust that recently replaced my original, TOR can.

As I've already mentioned, my primary objective was to reduce/eliminate the reoccurring cost of replacement OEM/disposable filters. To me, the cumulative cost savings over the life of my Sprint would be substantial... BTW, I've never run K&Ns in any of my cars or trucks, mainly because the disposable automotive filters cost a small fraction of what Triumph OEM filters run, so the savings aren't as great... economies of scale, I suppose.

Since I already own the damn thing, I'm first going to try and make the K&N fit better by fabricating a seal out of weatherstripping foam or rubber. If that works, then great; if not, I'll be going back to the paper element disposables and maybe give OnD's approach a shot... recognizing that while the air may be free, the filters sure aren't! [BTW OnD, you're too young to be retired, so how DO you find the time to come up with and better yet, execute all your clever (and I'm not being sarcastic, here) ideas? I'm jealous!] Once the seal issue is properly addressed, it may resolve my hesitation/stumbling problem; I guess I'll find out this weekend...

Also, as a complete aside, the absolutely easiest and best way to clean the soot/discoloration off your Trident exhaust's alloy tips is (drumroll, please).... acetone! First, let the tips cool to ambient temperature (for some reason, it doesn't work well when theyr'e hot), wet a paper towel with it, and simply wipe, then toss: it comes right off, with no rubbing, scrubbing, or polishing necessary! I guarantee it's the easiest clean-up you'll ever perform! I keep a can of it handy and wipe the tips before almost every ride, so they're nice and clean, hiding the center tip's reduced flow, rendering all three cosmetically uniform.

Thanks to all for your responses,
Cheers!
 

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The K&N did not fit my bike so I used the BMC. It fit perfectly.
 

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Discussion Starter · #20 ·
The K&N did not fit my bike so I used the BMC. It fit perfectly.
If I can't get the K&N to seal properly, I'd be interested in the BMC option, provided it works well and costs less than OEM. Do you recall what they run, and what's been your experience with that brand? BTW, am I correct in assuming that BMC filters are paper element disposables, and are there any issues? Some of the feedback hasn't been glowing...
 
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