EFI Speedmaster Jerky under 25mph - Triumph Forum: Triumph Rat Motorcycle Forums
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  • 1 Post By kiloTHREE
 
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post #1 of 9 (permalink) Old 07-30-2019, 01:18 PM Thread Starter
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EFI Speedmaster Jerky under 25mph

I've been fighting with commuter drive-ability on my new to me 2012 speedmaster since purchase a month ago.
The problem rears it's ugly head when driving under 25 freedom units per hour, in 1st or 2nd gear which puts me around 3-4k rpm, 3rd gear is too low for the speed.
On a dead cold start the problem will not be present, but 5-10 minutes into a drive it becomes apparent.
Symptoms are a vigorous jerky give and take at a steady 1/8th throttle input.
I can roll on/off throttle without fuss, but maintaining a smooth consistent pace is not possible.

This bike has always had this along with terrible throttle snatch.
The throttle snatch was cured by tightening the chain, re-enforcing the cush drive, a TTP stage 1 tune/filter, but not the symptoms as stated.
Currently the bike has AIS and O2 lines/sensors removed and plugged. no CEL's.
So far I have synced the throttle bodies various times, ran adaptations, set TPS, raised and lowered TPS voltage.
Outside of the stated problem, the bike runs terrific. 40 mpg across the board, no backfires, no problems starting...
It's the slow speed traffic that is killing the experience.

I am out of ideas, willing to try anything to clean out the demons.
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post #2 of 9 (permalink) Old 07-30-2019, 01:51 PM
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Freedom units killed me get it remapped
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post #3 of 9 (permalink) Old 07-30-2019, 02:12 PM Thread Starter
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TTP stage 1 tune/filter.
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get it remapped
Way ahead of you sir.
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post #4 of 9 (permalink) Old 07-30-2019, 02:48 PM
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Way ahead of you sir.
Yea, but it doesnt seem like that map is doing a great job?
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post #5 of 9 (permalink) Old 07-31-2019, 07:38 AM
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Way ahead of you sir.<img src="https://www.triumphrat.net/images/TriumphRat_2015/smilies/tango_face_wink.png" border="0" alt="" title="Wink" class="inlineimg" />
Yea, but it doesnt seem like that map is doing a great job?
Fwiw my Bonneville SE also has jerky low rpm light throttle behavior with TTP tune 2 2-1. Just remapping doesn't absolutely fix it. It doesn't bother me enough to try to modify the map with tuneecu just because the remapping process including the reset adaptation is so tedious and time consuming. Just one of the ways I was not completely satisfied with the TTP map. It's better than stock but far from perfect.

'12 Bonneville SE - mild mods
--
I write better than I ride. -- http://joshkarnes.net -- http://joshkarnes.blogspot.com
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post #6 of 9 (permalink) Old 07-31-2019, 08:23 AM Thread Starter
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I have the time, just not the knowledge yet to modify the map myself.
Hopefully I can scrape a few minutes here and there and fine a guide to tuning the map.
With the rest of the tune so well, I hope back to back tuning without a dyno can be done.
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post #7 of 9 (permalink) Old 08-08-2019, 09:07 AM Thread Starter
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Further development, now that its not nearly as hot out the issue is becoming less noticeable. Anyone have any pointers on editing the map or I read something about relocating the air intake sensor but can't seem to locate it again.
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post #8 of 9 (permalink) Old 08-08-2019, 10:31 AM
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Further development, now that its not nearly as hot out the issue is becoming less noticeable. Anyone have any pointers on editing the map or I read something about relocating the air intake sensor but can't seem to locate it again.
If you found it once you can do it again! Running worse in hot ambient temps would suggest richness at idle.

Last edited by Back2-2; 08-08-2019 at 11:31 AM. Reason: Removed wording. We do have ladies on this site.
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post #9 of 9 (permalink) Old 08-28-2019, 08:09 AM Thread Starter
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If anyone runs across this post for future reference, we got this all sorted out thanks to Mike at triumph twin power.
Turns out the bike was actually too lean, Mike richened up the low and and everything is perfect.
I really miss carb'd bikes, I could do more myself but Mike is an excellent resource.
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