TE 310 1st Ride - Post break-in thoughts?

So I got to take the new bike out this weekend for a few break in miles, and overall, I like it a lot. The bike turns like no other I've ridden, and really like the egros and the way the bike feels, even at 6'-1". I'm not conviced the bikes as heavy as the books/brocures say it is at what, 260 lbs? Sure felt good coming off a KTM 450 EXC! On that note, also felt light on power, but very much to be expected, so the comparison is a bit bogus. Living in AZ, we ride anywhere from sea level on up to 9,000 ft or more in the high country. One of the things I was so excited about is the EFI and not having to deal with jetting issues, however, I am a bit confused on why the bike runs like a champ at home in Phoenix, but tends to act like it's running to lean up around 6,000. The power up kit has been put in the bike, and the spark arrestor plug is in place. It's not clear to me as to why we can un-plug the O2 sensor as part of the power up kit and the EFI still knows how to compensate for elevation, but I'm wondering if that has anything to do with the diffenece in how she runs from low elevation to high? How does the bike know how change or adjust the air/fuel mixture? I ran the bike without the spark arrestor plug for a bit to see if there were any performance gains to be had, but it's too early to say really. Didn't want to hammer on it to hard for the first few hundred miles and having the cork in place is probably a good way to insure I don't! Being fresh out of the box, it's pretty obvious the bike needs time to "loosen" up. Bottom end is well, weak, but the midrange is a hoot! Pulls real clean and doesn't do anything unexpected coming out of the hole from corner to corner. Liked that a lot. Dicing in the twistys between the trees on a bike that's not figting to jump out from under you is kind of nice! Better than that, it's AWESOME! Hill climbing, well, that's going to take some adjusting to as well. Not that it didn't climb everything we came to, but it's definitly a lot mellower than I'm use to. The gearing is way low for my taste though. If not mistaken, the counter is a 13, rear 50. Doing a lot of shifting, which again, to be expected on a smaller bore. After the bike's good and broke in, I'll make the decision whetehr or not to add a tooth to the counter, or drop a couple in the rear when I'm not afraid to hammer on it on the uphills, but till then, I'll say it's adequate for trail riding. Don't expect to be happy at much over 45mph on the asphalt though as the hand vibration is substatial. Again, no surprise, IT'S A DIRT BIKE, not a street bike! Not a fan of the way the exhaust comes out as far as it does on the left side. My boots have more than a few burn marks, and my pants have a few new holes no thank you very much. Not a deal breaker for me, but something I'll be keeping an eye on. So, the moral of the story is, I like the bike a lot, but it's hard to really evaluate this early on to give the bike it's fair dues before it's good and broken in! Thoughts on what to expect to see/feel as the bike breaks in more from fellow TE 310 owners??

If you have the stock (real shiny) mid-pipe guard, get a better one like Uptite or Motorsportz. From what I've seen the guard doesn't protect much and you're not the first to complain.

My TE 250 is quite a bit less lively at 8000 ft. No bike or car will put out the horses at that kind of altitude. You might be getting 2/3 the horsepower.

You might like to have a better throttle tube to reduce some of the vibration and make the power smoother to apply. Has a roller bearing on the end.

Wow, that does come as a bit of a surprise, regarding the reduction in ponies at elevation, being that drastic that is. Haven't ridden it in the valley which is closer to sea level, so anxious to compare notes. The only exhaust guard I've seen for the header pipe comes from pirieper products and it's carbon fiber ( the guard by the O2 sensor).Didn't see the ones from Motosprots or Uptite on their web-site. Do the throttle tubes really make that signifigant a difference? How's the performance compare before/after getting some hours on the motor. They loosen up much, or is the performance pretty much what you can expect from the get go? I know every motor loosens up, but wonder just how tight these things are right out of the box. Appreciate the feed back.

has the throttle block (stop) been removed?

Yeah, for sure. Did the whole power up kit that came with the bike as well.

George did the powerup kit on one and rode it in the back alley. It pulled the front wheel off the ground....a 250. Quite a bit less vibration with the throttle tube at the right hand bar. They seem to take till about 2-3000 mi. to be fully broken in.

Some of Uptite products on my bike.

http://www.me.com/gallery/#100024

If you have removed the O2 sesnor then the bike cannot run closed loop (where the ECU adjusts fuel load delivery to meet a lambda target). It is running on an open loop set of maps- which should still be based on air density, just not lambda 1 as a target(14.7:1 A/F), probably closer to lambda .8ish (12:1). The lack of power is most likely due to reduced air density. Im at 6215 ft above sea level- our ambient air pressure is routinely 800 to 810 mb, where at sea level is 1000 +/- 10 mb. You are probably just really making 15 to 18% less power.

Re-visiting the calculator it turns out to be about 25% loss at 8000 feet, not the 1/3 or 33% I was estimating. 10,000 feet is where that happens

http://www.slowgt.com/Calc2.htm#BasAltCal

All above my head, when talking open/closed loop, but would it make sense that running with the O2 sensor in place for rides at elevation would be key to getting the bike to run properly without resetting the map programs already in place? Bike appears to run very well at home where the elevation is closer to 1,000 ft above sea level with O2 unplugged. If plugging the O2 sensor in to ride up in the high country is all I need to do, I can live with that. Not convinced my local dealers an expert in terms of tuning these bikes just yet.

I would call one of the experts and see what they say; Halls, Taskys, Uptite.....Congrats on the bike and please keep us posted.

The FI system has to measure air mass some way- its probably a speed/density system that uses RPM and a vacuum/pressure sensor on the manifold.

Disconnecting the O2 creates an open circuit in the heater element and probably tells the ECU to run open loop, that or a lack of any voltage on the input to the ECU does the same. In any case- open loop means rich- closed loop means lean. I doubt hooking up the O2 will make anything better at high altitudes.

FI is self compensating for mixtures, they will always be hyper accurate vs a carb- but it cannot make up for air density. "Thin" air at altitude has less O2 to catalyze fuel, simple as that.

It is not possible to make the same power at 6000 feet as at zero feet, even at the same lambda (air fuel ratio) unless your in cylinder air charge density is the same. You need a turbo ;-)

If its a normally aspirated engine we are talking about then the math is very simple. Its essentially a straight up air density table. See the image link. If at 10,000 feet the air density value vs sea level at a standard day is .69, then a 100 hp engine will make approximately 69 hp at 10000 feet. This is making is overly simple and things like temp, humidity and weather pressure systems all play a role in a specific days effect. These charts are all corrected back to what is called a "standard day" 70 F at 1012 mb and an air viscosity of 17.3 µPas.



100 hp engine plotted from 0 to 10000 feet, direct correlation to the air density chart:

Wow what a steep slope, I didn't know it was that steep. Thanks for the post/graph.

That's all good information, thank you. Is it safe to say, since the bike runs so good in the valley where I do 80% of my riding, I'm just going to have to live with the lean condition I'm experiencing at elevation, or... Is it possible to put the dual map switch on and have the 2nd map adjusted to meet the needs of 6,000 ft or so? Just trying to figure out whats the best way to get the most without buying the mapping software, or having to take the bike to the dealer every time I want to go up north! Maybe I just ride it and deal with it. It's not like it's a turd by any stretch!

Your bike is not lean at altitude- it feels "lean" because its making less power vs sea level. The bike is measuring the air density no matter where you ride and making fuel load delivery calculations many times a second.

O2 sensor plugged in = lambda 1 as a target fuel ratio (14.7:1) "lean"
O2 sensor unplugged = lambda .8 as a target fuel ratio (12:1) "rich"

Lambda 1 is ideal for emissions, lambda .8 is ideal for power. Leave the O2 unplugged for max power no matter where you ride. Just remember the higher you go the less power you will make with a normally aspirated engine.

Nice review

I suspect, coming off a KTM, much of what you're feeling is more the closer ratio transmission than it actually being geared to low or engine size.
(however it could still be too low for your riding style/conditions.)

The Husky's are definitely closer spaced between gears than the EXC's and you'll likely find yourself doing more quick short shifting, but you adjust to it. Personally I find the close ratio better for mountain trails and/or tight conditions and easier to keep in the meat of the powerband.
When riding a friends geared down 525EXC on faster paced steep/switchback trails, I find myself shifting between 2nd/3rd quite a bit, where on my stock geared TE510 I typically get into 3rd and can leave it there longer until we hit the straights and open them up......at this point the closer ratio has quicker acceleration, but pretty sure the EXC has more top end.
(at least we assume so based on paper. Around here, not too many places to try to run much over 80mph in the dirt, to know for sure.....plus while the Husky may be stable at speed, I'm not so sure either of us want ride a KTM w/o steering stabilizer at that speed anyway)



For HP loss, a reasonable rough estimate is about -3% per 1000ft.....as above table/calc's probably show.
Think that appiles not only normally aspirated engines, but also for my old out of shape body, and maybe I can add another -1% per year past 40

Yeah, but wouldn't air resistance be lower at altitude too, so you'd be able to "cut through" a less dense atmosphere......