make a donation to the fz1oa
fz1oa chat
fz1oa picture uploader
maintain your own photo albums
locate fz1oa members
Members Assistance Guide
search the entire board
click here for fz1oa web site home page
register a new account, it's free!
fz1oa store
email the fz1oa webmasters
read the fz1oa guidelines
read the fz1oa policy
open pat's fz1 site in a new window
open iowaz fz1 site in a new window
technical tips

Go Back   FZ1OA Message Board > FZ1 & Fazer Owners Association > General Motorcycle Discussion

Reply
 
Thread Tools Display Modes
Old 11-01-2018, 10:55 AM   #1
reubswinks
Registered User
 
reubswinks's Avatar
 
Join Date: Jun 2013
Location: Grand Haven, MI
Posts: 336
Carb four strokes need less attention than 2 strokes in regard to ambient temps?

I have always wondered why nobody really talks about jetting changes on our motorcycles when it comes to ambient temperature change. In Michigan I run my motorcycle from 100+ degree days, down the into the 30s. I have never really heard of anyone saying we should we changing the jetting for the change in temperature.

When I ride my two stroke dirt bike, it seems every 10 degree change has me at least playing with the air screw. Changing 50+ degrees I would certainly be looking at changing the jetting.

Whats the difference? Why are 4 strokes seemingly less prone to damage when running leaner. Or should I be more concerned about my motorcycle and changing the jetting?
reubswinks is offline   Reply With Quote
Old 11-01-2018, 10:58 AM   #2
fermic37
Registered User
 
fermic37's Avatar
 
Join Date: Jan 2012
Location: Central PA
Posts: 2,621
They are just less sensitive. I still made needle and air screw adjustments on my
Yz450 and my gen1.

Two strokes can be finicky some times, and if too lean you can burn up your piston. Won’t really happen on a four stroke.
fermic37 is offline   Reply With Quote
Old 11-01-2018, 11:03 AM   #3
reubswinks
Registered User
 
reubswinks's Avatar
 
Join Date: Jun 2013
Location: Grand Haven, MI
Posts: 336
Quote:
Originally Posted by fermic37 View Post
They are just less sensitive. I still made needle and air screw adjustments on my
Yz450 and my gen1.

Two strokes can be finicky some times, and if too lean you can burn up your piston. Won’t really happen on a four stroke.
Yeah...I guess I am curious what makes them less sensitive and why they aren't as prone to burn up. I suppose making air screw adjustments on my fz1 might not be a bad idea. I just don't see it talked about much in regards to temps.
reubswinks is offline   Reply With Quote
Old 11-01-2018, 11:13 AM   #4
grommet
kinetic mentality
 
grommet's Avatar
 
Join Date: May 2011
Location: hangin' with Toto
Posts: 12,173
IME, because the change in performance (negligible, as far as I can recall) is not enough to justify the effort.
__________________


Partly stabilized, partly curious.


Be your own man; don't be an owned man.

Some people would rather be dead than wrong.
grommet is offline   Reply With Quote
Old 11-01-2018, 01:40 PM   #5
iluvmyfz1
Just enjoy the machine....
 
iluvmyfz1's Avatar
 
Join Date: Jun 2011
Location: Buford, GA
Posts: 4,828
Atmospheric pressure, air density, and the constant velocity carbs on our Gen I's play well together, unlike the cable operated slide on most 2-smokes.
__________________
-'03 FZ1- "Xena"- Custom Orange/Red paint- FuzzyOne mirror mod- SW Motech QR racks- Givi E460 top- E21 side cases- SS brake lines - Scorpion slip-on- R6 shock- Throttlemeisters- Sargent seat- R1 shift arm- Custom sprocket cover- Cheap ass battery- Extended passenger pegs - Gauge of Eternal Coolness - Valtermoto Rearsets - HIDs -
iluvmyfz1 is offline   Reply With Quote
Old 11-01-2018, 01:44 PM   #6
NickBrewer
Registered User
 
Join Date: May 2007
Location: Wasilla, Alaska
Posts: 548
Keep in mind that a two stroke engine has a combustion event every revolution of the crankshaft, a four stroke has a combustion event every other revolution.

Combustion events cause lots of heat, therefore a two stroke generates much more heat within the cylinder that has to be dissipated somehow. To a certain extent, both engine types use the (relatively) cool fuel/air mix to help cool the piston, but a two stroke just has far less time for cooling to take effect.

On top of all that, a two stroke does not have a crankcase full of (relatively) cool oil underneath the piston to help cool it.
__________________
Nick Brewer
NickBrewer@msn.com
1986 Yamaha SRX-6
2016 Yamaha XSR900 60th Anniversary
NickBrewer is offline   Reply With Quote
Old 11-01-2018, 03:08 PM   #7
fermic37
Registered User
 
fermic37's Avatar
 
Join Date: Jan 2012
Location: Central PA
Posts: 2,621
You can Install a lectron on it and not worry!
fermic37 is offline   Reply With Quote
Old 11-01-2018, 03:44 PM   #8
Duken4evr
Map Maven
 
Duken4evr's Avatar
 
Join Date: Oct 2006
Location: Parker, CO
Posts: 8,851
The old Keihin carb on my '13 TE300 works great with a JD jet kit in it, have ridden in the cold in Moab at around 4,100 feet all the way up to 12,000 feet. It may not be ideal, but it easily falls within "good enough" in a wide variety of environments. A buddy has a '17 300 with the Mikuni carb and he is constantly in jetting Hell, so it depends a lot on the carb for two strokes. The Mikuni is crap (at least as delivered by KTM), the Keihin on the older 300s is great, and the Lectron is even better evidently.

Going to Moab next week, actually. I do fudge a little when I go there when it is cold, and swing by Bandimere Speedway and get some cool purple 110 octane Sunoco race gas to mix in 50/50 with premium as it is on the way out of town and buying it there is a lot cheaper than buying a can of VP at the MC parts emporium. Runs super crispy on that stuff, even if it is a little lean, it does not care
__________________
With experience of a tortured youth, we turn up the music and go in search of the truth.

Wise man said - "Don't go bagger too soon".


Get your FI maps right here:

http://www.mediafire.com/download/nr...1_Map_Pack.zip

Akra full exhaust mindless stationary rev out Video: http://www.youtube.com/watch?v=w5UNYBqHd7M
Duken4evr is offline   Reply With Quote
Reply

Go Back   FZ1OA Message Board > FZ1 & Fazer Owners Association > General Motorcycle Discussion


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -7. The time now is 08:15 PM.


Questions? Comments?
Click on name below to contact via PM
Rabeet (Admin) Desmo (Admin)

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Website and Message Board Contents Copyright 2001-2007 FZ1OA
The marks YAMAHA® and FZ1® are used under license from Yamaha Motor Corporation, U.S.A.
The information on this web site is NOT approved or endorsed by Yamaha Motor Corporation in any way.
Page generated in 0.06369 seconds with 11 queries