EFI or carb WHICH ONE!

mikenva

mikenva

Rocker
I dont know much about the efi triumph is useing ,if the throttle boddies are big enough,someone will come up with a remap that will blow all our carb bikes away.If there to small like our stock carbs are they wont run much better then the carbs do.
like the dude said sometimes its best not to buy the first year out till the bugs are worked out.H P efi is far better then carbs it can change mix with weather and keep its self tuned ,You can allso run higher compression with efi .If triumph would get smart like the jap bikes we could have 12to1 bonnies with efi that turn 10,000 rpm and make way over 100 hp.Hds motor design is 50 years out of date ours is only 20 years out of date lol.
 
ivar

ivar

TT Racer
mikenva said:
I dont know much about the efi triumph is useing ,if the throttle boddies are big enough,someone will come up with a remap that will blow all our carb bikes away.If there to small like our stock carbs are they wont run much better then the carbs do.
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From what I read somewhere, Triumph's using Keihin carb bodies as FI throttle bodies , to retain that "authenic look" I've got no idea if its the same diameter as the current carbs.

Myself I prefer carbs for now. Often, throttle response is both better and smoother with carbs vs EFI, some EFI systems having a nasty on/off action at certain rpms. (But Triumph starting to get quite some experience using FI on their triples, they should be able to work out the bugs of the system)
 
jamesbgood

jamesbgood

Scooter
I want to thank everyone for the advice :)
Today a dropped a gee on the black/gold 2009 EFI thrux and when I get all my ducks in a row I'm picking her up sept 2nd :rocks:
I figure if I don't like the EFI I can rip it all out and throw a carburetor in.:d
But for now.....I don't give a shit cause I'm the owner of the sexiest bike I've ever seen!
motion.gif
 
Old Scratcher

Old Scratcher

who?
Hey congrats JBG. It's about time you got yourself a ride. I don't think you'll be dissapointed with the EFI. But I don't think you could convert it to a carbed bike just by fitting carbs to it. I would think that you'd have to change the whole engine management system too. & that would be quite costly.
So I really do hope you like the EFI. (can't see why you wouldn't)
 
thruxiegirl

thruxiegirl

TT Racer
jamesbgood said:
I want to thank everyone for the advice :)
Today a dropped a gee on the black/gold 2009 EFI thrux and when I get all my ducks in a row I'm picking her up sept 2nd :rocks:
I figure if I don't like the EFI I can rip it all out and throw a carburetor in.:d
But for now.....I don't give a shit cause I'm the owner of the sexiest bike I've ever seen!
motion.gif
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You live in Canada go climb some big Mountains and don't worry about the bike having any asthma attacks.

That color is sexy. Post pics when you can. Does it have bars or clip ons?
 
jamesbgood

jamesbgood

Scooter
thruxiegirl said:
You live in Canada go climb some big Mountains and don't worry about the bike having any asthma attacks.

That color is sexy. Post pics when you can. Does it have bars or clip ons?
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yodel eh hee who yup looking forward to some nice rides through the :canada: mountains :)
and yes it has bars instead of clip ons
 
SLEDHEAD

SLEDHEAD

Two Stroke
Unfortunately in laymens thinking EFI is presumed to be the perfect fuel management system...But it is NOT...It is however a tool used by manufacturers to meet EPA regulations and eliminate warrenty claims related to lean jetting conditions with guys who tinker with carbs. I'll try to explain in as simple terms as possible....2 of the most important numbers that are watched when making a pull on a dyno are the B.S.F.C and the A/F RATIO...On a 2 stroke engine optimum performance is reached with a bsfc # at or near the low 0.60's...A/F ratios are percieved to provide best performance at or near 14.1
The higher the bsfc # the richer the fuel mixture is in the combustion chamber. On the other hand the lower the a/f # is means that the combustion chamber has richer mixture. Manufacturers DO NOT setup the computerized efi system in this manner...A GOOD CARB TUNER can produce better H.P./T.Q. numbers across the entire rpm powerband opposed to factory calibrated EFI...

Case in point...One of my snowmobiles has a 2 stroke 700cc twin cyl with efi...I have a copy of the dyno run of that engine as it is sent out to the customers with the FACTORY calibrated efi programming...I'll try and download it here and explain further....
 
SLEDHEAD

SLEDHEAD

Two Stroke
SLEDHEAD said:
Unfortunately in laymens thinking EFI is presumed to be the perfect fuel management system...But it is NOT...It is however a tool used by manufacturers to meet EPA regulations and eliminate warrenty claims related to lean jetting conditions with guys who tinker with carbs. I'll try to explain in as simple terms as possible....2 of the most important numbers that are watched when making a pull on a dyno are the B.S.F.C and the A/F RATIO...On a 2 stroke engine optimum performance is reached with a bsfc # at or near the low 0.60's...A/F ratios are percieved to provide best performance at or near 14.1
The higher the bsfc # the richer the fuel mixture is in the combustion chamber. On the other hand the lower the a/f # is means that the combustion chamber has richer mixture. Manufacturers DO NOT setup the computerized efi system in this manner...A GOOD CARB TUNER can produce better H.P./T.Q. numbers across the entire rpm powerband opposed to factory calibrated EFI...

Case in point...One of my snowmobiles has a 2 stroke 700cc twin cyl with efi...I have a copy of the dyno run of that engine as it is sent out to the customers with the FACTORY calibrated efi programming...I'll try and download it here and explain further....
Click to expand...

Here's the dyno run on that particular engine...Take notice of the bsfc #'s...Horribly rich thru out most of the powerband ( best results around the low 0.60's)...Same goes for the a/f ratios ( best results around 14.1)...This motor is being pumped with an exceptional amount of fuel...This is done by the manufactuers designed efi program to lower the combustion chamber temps. Lower combustion chamber temps help eliminate egt (exhaust gas temps) temperatures associated with lean burndowns when the temps rise above approx 1250 degrees in the exhaust system. On this engine, an aftermaket fuel mgmt programmer can be used to manipulate the factory calibrated settings.
 

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ivar

ivar

TT Racer
I agree w/ sledhead that EFI is not neccesarily better than carbs.
But with EFI , one can usually get away with using bigger throttle bodies, and still maintain a good low end response. Like the snowmobile below, with carbs it would probably be equipped with Mikuni TM40's , while I believe the EFI throttle bodies used are 46mm.

As for the snowmobile dyno chart, snowmobiles have earlier been subject to less strict emmissions regulations. According to the current (EPA2006?) regulations, they would not get away with putting out a engine with bsfc numbers in the .8 range. (I'm also surprised that it actually makes 140HP , with the gas literally running out the exhaust pipe)
 
Soulrebel

Soulrebel

Street Tracker
SLEDHEAD-"On this engine, an aftermaket fuel mgmt programmer can be used to manipulate the factory calibrated settings"

So with something like the power commander/tuneboy etc., you an easily manipulate fuel, timing and rev limits at all points on the power curve. I fail to see why this is less effective/tuneable than a carb, other than limits on the amount of air you can flow, which we run into on the stock carbs anyway. You may have to wait a little while for someone to make a specific one for the new bonnie, but it will come.
 
SLEDHEAD

SLEDHEAD

Two Stroke
Soulrebel said:
SLEDHEAD-"On this engine, an aftermaket fuel mgmt programmer can be used to manipulate the factory calibrated settings"

So with something like the power commander/tuneboy etc., you an easily manipulate fuel, timing and rev limits at all points on the power curve. I fail to see why this is less effective/tuneable than a carb, other than limits on the amount of air you can flow, which we run into on the stock carbs anyway. You may have to wait a little while for someone to make a specific one for the new bonnie, but it will come.
Click to expand...

I based my explaination on FACTORY EFI PROGRAMS...Powercommanders/Boondocker box aftermarket programmers can fine tune factory efi calibrations...($400.00)

I'll be curious to see the Triumph "BASELINE" efi calibrations when someone puts one of these motors on a dyno....
 
jamesbgood

jamesbgood

Scooter
:shh: I'm not supposed to say anything but a fly on the wall told me today that a certain aftermarket dealer is getting the Dynojet PowerCommander this week for dyno testing.

remapping is getting closer EFI er's
 
S

Skidmark

Scooter
09 EFI Bonnie

I have only put 1 tank of fuel through my new bonnie but it revs up well compared to my 08 Thruxton (Staintunes, AI and snorkel removed, K+N filter). It also trickles through traffic smoothly. It looks like it will be a keeper for commuting with all the go fast stuff going on the the Thrux.

But it is really quiet.

Skiddy
Brisbane
 
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