Triumphrat

denny

I'd like to see some detailed pics of that modification.

my bikes have no room for a rear plenum on the right side because of the battery location. So some pics of that would be very helpful to some of us looking for an airbox mod that make alot of sense. I agree that opening up the airbox is not an easy approach. The jetting after that certainly takes alot of fiddling to get it just right.

My TBS had K&N pods when I got it. It was tuned to run decent in Rhode Island, near sea level. I moved it to Indiana, approx 2,000 feet above sea level and it didn't run so good. I returned it to stock and it's OK, but I am looking for something a little better.

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Cheers,Denny

Rhinoe

OK, What are plenums and what are snorkels?

- Thanks, Ryan

Mojoinco

On the airbox, a lot of folks have installed the Trophy unit. I believe the Trident and maybe even the older S3 may have the same box (a search of part numbers will tell). The filter has a slightly larger area. If you search you will find some pics and threads on this. Others have drilled the box (mine was drilled with a series of 1/4-5/16" holes) under the side covers in the rear section (stock TBS box). I also removed the tube connecting the secondary airbox. Other than that I haven't done any work to increase power, as it came with the airbox mods, D&D 3 into 3's and an aftermarket filter. The needles were supposedly raised, and the airfilter is a blue colored k&N style (larger filtered area though). Now that I removed the secondary box link (I wanted tool space) it has an ever so slight mid-top range lean throttle when it is cold out (which it has been for far too long this year) and the engine is cold.

Hope this helps just a tiny bit. And if you want to move the battery a bit, I can send pics of a mod I did over the winter (waiting for a member pic page).

It seems that from the casual observer there has been a fair amount of discussion based on two or three premises or perspectives:

>Differences in tuning with two different styles of dynos (info is around the web on this) and interpretation of those results.

>Not enough dyno info. Given and accepted by all.

>Differences in technical perspectives. Which side is the left side kinds of references ('right' isn't so important as knowing where you are referencing from).

>Folks getting stuck with the argument, not the solution. I work on expensive computers and get stuck on/in this occasionally (sometimes it's even my fault). Doesn't matter which came first, the chicken or the egg when you need to shovel the poop.

Ok girls, a little less foam, and keep out the 'I saids'. This has generally been an educational (if not wordy) thread. All your technical considerations are appreciated as anything that encourages a person to research what is read makes us all smarter. Kind of like reading Kipling or Shakepeare (sp) at times, but enlightening all the same. Increases the body of knowledge or something like that....


So BadMouth, we are waiting for more info on your testing. As the rest of us get to learn from your wallet!

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Yee-haaaaa!

jimmyj900

Moto, your first couple of posts showed you to be agressive and confrontational and equally demonstrated that you don't know jack about the 885 Classics. I wasn't interested in getting drawn into a point by point argument with you and I'm still not interested in that.


But now that you've worked off most of that initial agression and calmed down a bit...

The Classics line was apparently designed to fit into a specific horsepower niche for the European market. As such, they have serious intake and exhaust restrictions as well as what's probably the mildest cam put into a street motorcycle since the '70s.

The best horsepower you can get from a Classics model is in the range of 60-62 RWHP with the stock airbox, 8750 rpm igniter and the 2:1/1:1 exhaust. That's because the stock airbox only has a single inlet about 1-3/4" in diameter and can't supply sufficient air for larger jets. It takes more air to burn more fuel and produce more power, but the stock air intake system puts a very stiff limit on air delivery, so the maximum usable main jet size with the Keihin carbs is a #102 and that will be a bit rich here and there. #40 pilots work well with the stock airbox but #42 pilots also tend to be rich in spots.

The same bike with ANY modified air intake system (pods, chopped stock filter box, chopped Trophy filter box) will be 70-75 RWHP due to the limits of the exhaust system.

Putting a bigger cam (more lift, longer duration) into the same bike with a modified air intake will (again) produce a maximum of 70-75 RWHP due to the limitations of the exhaust system. The bigger cam can make a significant 'seat of the pants boost' in the midrange (4,000-6,000 rpm) but has virtually no effect on the top end. The bigger cams cause considerable problems with the low and midrange when coupled with intake mods as Badmouth's dyno run shows.

I'd also point out that maximum horsepower is completely misleading standard for determining the performance of a street bike. Horsepower is directly related to rpm so the peak horsepower is usually outside the normal street riding range. The useable indicator of rideability is the flatness of the torque curve -- not the maximum horsepower -- and that's what most of us are trying to address. (Of course, a few more ponies never hurts...)


The big problem we all have with the Keihin CVK carbs is that they're 'proprietary.' Tuning parts are unavailable beyond the main and pilot jets (multiple suppliers) and either the Factory Pro or stock needles. Alternate needle jets are unavailable, the pilot air jets are fixed and not replaceable and the main air jets are also fixed, so we're pretty limited on what we 'Joe Average' wrench heads can do with the carbs.

The alternative is to install something diddleable like FCRs, but at about 1/3 of the value of the bike that's generally outside our price range.


Another problem most of us face is a lack of dyno availability. We diddle the carbs, look for seat of the pants performance, diddle the carbs some more and when it 'feels pretty good' go for a dyno run. Then we find out that the 'backside dyno' isn't very accurate since the results are relative rather than absolute and we try again.


You also haven't provided 'hands on' suggestions as Badmouth was originally soliciting. You've said you set up an Adventurer so how about sharing what you did rather than bombing us with technical minutiae?

While you were running in attack mode your initial technical points were incoherent but now that you've calmed down a bit you're making a lot more sense. You could be a big and appreciated asset to the group if you can keep the agression toned down.

Jim

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CAUTION: This post may have been altered and critical safety information deleted without the permission or knowledge of the author.

BadMouth

(since everyone else seems to be following the quote and reply format....)

"Even if I could tell you exactly what to do with your motorcycle, wouldn't you rather know how to do it yourself?"


I'd rather save a lot of time and money by learning what has and hasn't worked for others with the same engine.



"You know the adage about giving someone food vs. teaching them how to farm, don't you?"

I don't want to have to buy the whole farm just to get my one cow milked :razz:


"So BadMouth, we are waiting for more info on your testing. As the rest of us get to learn from your wallet!" - MOJO

You may have to wait a while as I'm taking it on a long trip in May and don't really want to mess with anything on it until after I get back.


I'm going to order a trophy airbox this evening. I'll get the airbox first and then see if it looks like there's any way to run the ductwork without it ruining the classic look of the bike. I need to reposition the battery anyway to squeeze the older/larger igniter in. I searched in the T3 sport touring forum and the concensus (that's a nice word) there is that the bike sounds cooler without the ductwork, but doesn't perform as well on the dyno.

I'm still thinking (in my layman's brain) that a 3 into 1 would improve my low end torque. I like the looks of the thunderbike pipe, but it would be nice to have something adjustable.

ecrabbit96

As stated earlier, and I think Jimmyj900 has pointed out in his last. The carbs in there stock mold can't possibly support the heavy mods unless as moto has pointed out, someone with the skills and equipment can modify certain static features of these carbs. Just because we can screw a 200 main jet in there doesn't mean it will work.
I love it when a young kid tells me he has a chevy 350 (stock) and he's put a 750 double pumpah on it. Thinks he's got a dragster, when in all actuallity he has robbed his engine of power. The 350 (stock) can really only support a 650, not until we adress all aspects of flow, from the airbox to the tip of the exhaust can we start pouring more money I mean fuel down the throat. A well tuned 2 barrel on this same engine will smoke the 750 setup.

Spooner

This thread is giving me a serious headache guys. The speed triple is looking more and more inviting....no more carb tuning... a USB cable and a laptop sounds like heaven!

On the other hand I must say I'm quite proud of my 78 rwhp and 59 ft/lbs which I got by doodling around myself...squeezing in the odd dyno run ofcourse.

Anyhooo....good luck! :hihi:

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S.P.O.O.N.E.R.

Huh?



Speedy MattHilda & Thunderasaki

BadMouth

Here's a link to the thunderbike pipes Clicky

Saigon 5 wrote "This was the cure for my very uneven set up, now I am back to a nice power curve, no flat, no dip. "

ecrabbit96

Static features as I refered to them would be the aspects of the carb that are molded or placed in the carb with the intent they will never be changed, or can't be changed. Barring ofcourse taking a drill to them. Dynamic components would be like the pilots, jets, etc... things designed to be modified or replaced.
A snorkle would actually be the very first inlet pipe on what I believe is refered to as a drop box. The piece that joins the two boxes, (drop box to air box) is mearly a coupling. The drop box is designed to allow large particals of debris to fall out of the air stream as it looses velocity through the box.

Saigon5

I was following this thread from a distance but now it seems that I can show you a dyno run that is somewhat similar to yours.

Here is a dyno run taken on a TBS with the following modifications.

Speed Triple 2001 cams, red or brown, depending on what colors one see.
Trophy air box with K&N filter, no additional holes.
Triumph off road pipes.
Jim's needle, no shims.
146-142-146 main jet
40to 42 pilot jets, I can't say exactly how big since I could not find any bigger than 38. 38 were drilled to a bigger holes.



As one can see, the same dip is in the same place. The main difference is on the jets. My previous experimenting with jets brought me to the 146. I tried, 120, 130,140 and finally settled on 146.

This dyno run has the same equipment, except the following changes.

Thunderbike header and exhaust.
Jim's needle with 1 1/2 shims.
Unfortunately I do not have the fuel air ratio on the run but I was present beside the screen when the run was taken. One can see in the power curve that it is a lot better and it is a lot closer to the original set up as seen on the last dyno run.




Here is the first dyno run made before I started to fool around. The only mod was the off road pipes.



All this to say that in my opinion, the solution to your problem lies in the header and while there I would try bigger main jets. It was clear that with the new header, the rich dip was not only gone but it was too lean until I added shims. I did use some small plastic washers that are equivalent to 1/2 shim. I did put 3 of those before the final dyno run.

[ This message was edited by: Saigon5 on 2007-04-20 19:01 ]

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