Choppy power band
-
I should report that the last weeks the sputtering has improved significantly without me doing much of anything.
Well, I did twist the air screw a bit, and my new main jets arrived and lie here on the table, and I am waiting for a Mikuni rebuild kit - but in the meantime the bike decided to behave better. It is weird.
It still hesitates a bit around 7000 before coming into force until 9500, and I can probably improve that with a bit of tweaking, but it is largely acceptable as is. And actually it feels like a bit more than 23 hp, comparing the seat-of-the-pants feel with my old '87 and '90 DT's. They would hesitate at 5000, then come alive at 6000 and lose breath at 8500.
I can't imagine that a 2003 bike that seems unchanged in design since 1989 would have anything like modern self-learning ECU tricks, right? I just assume the CDI box would be rather primitive. Right? Right...?
-
This post is deleted!
-
I should report that the last weeks the sputtering has improved significantly without me doing much of anything.
Well, I did twist the air screw a bit, and my new main jets arrived and lie here on the table, and I am waiting for a Mikuni rebuild kit - but in the meantime the bike decided to behave better. It is weird.
It still hesitates a bit around 7000 before coming into force until 9500, and I can probably improve that with a bit of tweaking, but it is largely acceptable as is. And actually it feels like a bit more than 23 hp, comparing the seat-of-the-pants feel with my old '87 and '90 DT's. They would hesitate at 5000, then come alive at 6000 and lose breath at 8500.
I can't imagine that a 2003 bike that seems unchanged in design since 1989 would have anything like modern self-learning ECU tricks, right? I just assume the CDI box would be rather primitive. Right? Right...?
@Hark_Ptooie no sensors around to learn from...
-
I should report that the last weeks the sputtering has improved significantly without me doing much of anything.
Well, I did twist the air screw a bit, and my new main jets arrived and lie here on the table, and I am waiting for a Mikuni rebuild kit - but in the meantime the bike decided to behave better. It is weird.
It still hesitates a bit around 7000 before coming into force until 9500, and I can probably improve that with a bit of tweaking, but it is largely acceptable as is. And actually it feels like a bit more than 23 hp, comparing the seat-of-the-pants feel with my old '87 and '90 DT's. They would hesitate at 5000, then come alive at 6000 and lose breath at 8500.
I can't imagine that a 2003 bike that seems unchanged in design since 1989 would have anything like modern self-learning ECU tricks, right? I just assume the CDI box would be rather primitive. Right? Right...?
@Mr-Shadi had the rev limiter cutting in at around 6000rpm in all the gears at one point. I know it’s not what you want to hear but it’s got to be worth checking, no?
Just try reconnecting it to see if it revs freely in the lower gears. If it’s the same then At least you can cross it off completely. Added bonus is I’ll shut up about the read switch 🤩 -
The engine pulls freely to redline on all gears. It was just around 7000 where it sputtered and coughed. Still does, but far less.
If there are no sensors, then the only remaining reason why it would run better now than before would be that I filled up with new gas. I suppose the old stuff had been sitting in the tank for a long time when I bought the bike...
-
The engine pulls freely to redline on all gears. It was just around 7000 where it sputtered and coughed. Still does, but far less.
If there are no sensors, then the only remaining reason why it would run better now than before would be that I filled up with new gas. I suppose the old stuff had been sitting in the tank for a long time when I bought the bike...
Could there be a chance that it’s affecting it partially? It’s not that big of a job to check and cross it off completely. Remember, the added bonus is I’ll shut up
… -
The reed switch is thickly wrapped in electrical tape and put far away from everything, as far as I know.
-
Just for closure I want to add that the sputtering went away by itself after a hundred kilometers or so.
I'm guessing old grime in the vaporizer that recent use dissolved. It had been standing in a garage for quite some time when I bought it.
Bike now goes like my old 1990 did, only even more cheerful what with the Athena expansion chamber.
…
