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I enquired to Alta about how their bike would go in a flat track event with 700M straights for 4 laps, thats about 18 seconds flat out followed by 5 seconds braking. They told me that it wouldnt last as thermal limiting would slow it down after 2 laps. Has anyone ever experienced the thermal limiting on their Alta (or someone else's Alta)?
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Edited Date/Time:
Yes thermal limiting happens when overheating of the sensors. Here’s a exclamation I received from Alta. https://p14.zdusercontent.com/attachment/818476/0QJQZok2mkNhZax3ca5Ex9u0W?token=eyJhbGciOiJkaXIiLCJlbmMiOiJBMTI4Q0JDLUhTMjU2In0..HROKXENTOTD7UGKyNX627Q.E_IFbdnAm8nw8gnu1qlwU8VWSYetVkNXXf9j5LB39ZHI0DqFYgSiphJoWd2FmMqhYoix5OUXHGiIP-cEKH-3w32J4jhfrKVrYSQ6lRJvB6aft_0CxrvQ7zzpxRMxDpYZvpxWK6dAltXcdv1HoCsYSz5iF6gxI9uX2sLy9Nq8NDN_pVdMPxR_9GNT5GBm7b2--2eN8Fij_qn0n8sjGNBUjDjBxQQtiS-7P9IIyWVw9RzYWmfK0XLBmcHyMr6F3lC4Jow-nSV5xWePj3LmVsxEow.N2JEwC9grqmKSEXHUOnN1w
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Fog 25 wrote:Yes thermal limiting happens when overheating of the sensors. Here’s a exclamation I received from Alta. ...more
fullysicmate wrote:Thanks, has it ever thermal limited while you were riding? Those parameters seem quite low.
It seams to happen when it’s real hot out and you are riding it hard. The warning light comes on and the power reduces a little bit. Still rideable. The power reduction is not as much as when you get to battery limiter ( low battery).
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Location: OH, USA
fullysicmate wrote:I enquired to Alta about how their bike would go in a flat track event with 700M straights for 4 laps, thats about 18 seconds ...more
It happens on my 18 MXR if i'm riding motocross at a track, constantly charging or riding it, and really hot out (90F).
If won't occur until I go through 3-4 ride-charge-ride-charge sessions.
It gradually cuts the power output, but will never completely "shut off"
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fullysicmate wrote:I enquired to Alta about how their bike would go in a flat track event with 700M straights for 4 laps, thats about 18 seconds ...more
Bigoldbeef wrote:It happens on my 18 MXR if i'm riding motocross at a track, constantly charging or riding it, and really hot out (90F).
If ...more
Do you think if you did 4 laps of a track that was essentially a barrel race with 700m straights it would do it?
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fullysicmate wrote:I enquired to Alta about how their bike would go in a flat track event with 700M straights for 4 laps, thats about 18 seconds ...more
Bigoldbeef wrote:It happens on my 18 MXR if i'm riding motocross at a track, constantly charging or riding it, and really hot out (90F).
If ...morefullysicmate wrote:Do you think if you did 4 laps of a track that was essentially a barrel race with 700m straights it would do it?
Not sure if it’s entirely possible, but you could potentially mount a fan between the front frame spars to direct more air to the battery pack?
I suppose it depends on what sensor heats up the quickest and triggers it.
You could try to get it as cool as possible before the start and maybe it’ll be fine?
If you're not mixing gas, you're not haulin ass.
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fullysicmate wrote:I enquired to Alta about how their bike would go in a flat track event with 700M straights for 4 laps, thats about 18 seconds ...more
Bigoldbeef wrote:It happens on my 18 MXR if i'm riding motocross at a track, constantly charging or riding it, and really hot out (90F).
If ...morefullysicmate wrote:Do you think if you did 4 laps of a track that was essentially a barrel race with 700m straights it would do it?
No. It only occurs after riding the bike & charging continuously for over 1.5-2 hours.
If I don’t charge I could ride in map 4 wide open from full - dead battery without ever hitting the thermal limiter.
It only occurs after continuous ride/charge cycles where the battery never gets a break to cool.
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Location: Ogden, UT USA
Edited Date/Time:
It seems to be happening to me more frequently now. First couple times it happened was on 3rd ride cycle on continuous ride charge ride. Then happened on 2nd ride cycle. This last weekend was the first time it happened on the first ride cycle at the end of the charge, the bike was charged a couple of days before. The previous times outdoor temp was in 80-90, this last weekend was in 70's. All of them at same track ridden in level 4. Bike is 2018 MXR
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Location: Pine Grove, PA USA
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Try a misting fan when charging it cools the battery down and have not had a problem with thermal limiting when using the fan.
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Location: Belton, MO USA
I read the technical sheet posted above and I have a question.
In the Midwest we often ride at 40° or sometimes a touch colder even on sunny days. Hand guards and hoodies are good tools to stay warm. However... is it really that bad to ride the battery under 50°? That’s the only chink in the Alta armor I’ve found yet- given that some of our very best riding days happen well under 50°.
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Jeff_Crutcher wrote:I read the technical sheet posted above and I have a question.
In the Midwest we often ride at 40 or sometimes a touch ...more
I wondered the same thing. Does riding cold weather affect it?
