|
11-28-2016, 12:11 AM | #1 |
Join Date: Apr 2016
Posts: 79
|
TT250 hiccup
I installed the aftermarket Ebay pipe, 47 tooth sprocket, opened up the air box and re-jetted the carb with a 112 main jet while lifting the needle up one notch from the stock position. The bike runs fantastic, except every so often while under load in top gear the bike sort of stutters for a fraction of a second which is like a hiccup in human terms.
It almost feels like the spark gets interrupted for a heartbeat, but I can't imagine what would cause that. It could be the fuel gets cut off from the intake momentarily- which I don't think would feel as dramatic as a hiccup - and there really is no explanation for that to happen. Perhaps it has something to do with the air injection system? Has anyone else experienced this sensation? Any ideas? Thanks. |
|
11-28-2016, 01:08 AM | #2 |
Join Date: Jun 2016
Location: Colorado
Posts: 1,107
|
You might want to try a larger main jet.
|
|
11-28-2016, 02:49 AM | #3 |
Join Date: Apr 2016
Posts: 79
|
Why would that be? More specifically, wouldn't a lean condition manifest itself as more of a constant lean situation rather than something that occurs every 60 seconds or so?
Also, has anyone tried using a 114 jet with my combination (I am at sea level)? If so, how were the results? |
|
11-28-2016, 03:08 AM | #4 | |
Join Date: Oct 2015
Posts: 75
|
Quote:
|
|
|
11-28-2016, 06:05 AM | #6 |
Join Date: Sep 2015
Posts: 436
|
I have 115-30 jets with similar mods on my Hawk.No more hiccups.
|
|
11-28-2016, 08:25 AM | #7 | |
Join Date: Jun 2016
Location: akwesasne, NY-13655
Posts: 2,220
|
Quote:
|
|
|
11-28-2016, 09:15 AM | #8 |
Join Date: Apr 2016
Posts: 79
|
Chuck - was your bike doing the hiccups also before you increased the jet size to 115?
Ariel - yes, it is the original carb and I did re-torque the flange bolts properly so I do not suspect any leaks there. What are the 'usual' symptoms of the air injector system failing? |
|
11-28-2016, 03:38 PM | #9 | |
Join Date: Jun 2016
Location: akwesasne, NY-13655
Posts: 2,220
|
Quote:
|
|
|
11-28-2016, 07:04 PM | #10 |
Join Date: Apr 2016
Posts: 79
|
|
|
11-28-2016, 08:15 PM | #11 |
Join Date: Jun 2016
Location: akwesasne, NY-13655
Posts: 2,220
|
I should have said hiccups when running at a steady speed. A roll-off hiccup is caused by a too rich Main jet.
|
|
11-28-2016, 10:59 AM | #12 |
Join Date: Mar 2010
Location: Volcano, Ca
Posts: 7,112
|
I'm with the others on the main jet being a good place to start. I'm at 3000' and am running a 112.5/25 (Mikuni) in Mrs 2LZ TT250. It pulls solidly all the way up the rpm range.
What elevation are you at? You may be able to easily justify a 115.
__________________
"Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350 |
|
11-28-2016, 11:36 AM | #13 |
Join Date: Jun 2016
Location: Colorado
Posts: 1,107
|
What would you think would be needed for a main jet at 8500 - 10000 feet? I have a new uncorked muffler a mikuni vm26 carb with a foam filter. Iam thinking maybe a 120?
|
|
11-28-2016, 12:51 PM | #14 | |
Join Date: Mar 2010
Location: Volcano, Ca
Posts: 7,112
|
Quote:
What jetting are you currently running? The stock Mikuni 100/20 that came with it?
__________________
"Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350 |
|
|
11-28-2016, 01:36 PM | #15 |
Join Date: Jun 2016
Location: Colorado
Posts: 1,107
|
ya the 100/20. I have a set of 10 jets going from 88 up to 125.
__________________
Bashan Blaze Mods: Alloy Rim's, Muffler, Mukuni VM26 Carb, Foam Filter, Tachometer, Volt Meter,LED Headlight, LED Blinkers |
|
|
|
|
|