Jump to content
Sign in to follow this  

Beta 4T engine starting issues & a different fix ...

Recommended Posts

I have one of the 2011 520RS (with stock exhaust) which can have starting issues at what seemed like random times. Usually engine does not spin or spins half a turn & stops. Usually starts by the 3rd start button stab with 5-seconds pauses between. +200 hours on oem battery & no wiring mods yet. Has been this way since new.

I was riding this past weekend where we camped at 2500 feet, but rode up to 8400 feet and back down again. 3 days in a row. I was making 2 fuel screw adjustments going up & down to keep the throttle response crisp.

I discovered during these adjustments that a too-rich fuel screw setting will CAUSE this starting problem. Each time I leaned the idle mixture to where it was just above a hanging idle (lean) sound when blipped, my starting problems went away. 100% of the time! It even started in gear with the clutch pulled in! :thumbsup:

Also, if you raise the idle speed slightly with this leaner idle mixture, the 520 no longer has TOO-MUCH engine braking just above idle. F*CKING YEAAAA!!! :D

If your 4T Beta does not start instantly when warm with no throttle, try turning your fuel screw in 1/4 turn (at a time), wait 5 seconds, and try again.

Catfish ...

Share this post


Link to post
Share on other sites

Interesting find, funny you mentioned this, when the temp was cooler here it started better, now it doesn't just start, it takes a few cranks which makes sense because it will be running richer with warmer weather

Share this post


Link to post
Share on other sites

Install the updated de-comp on the cam.

Later george

Share this post


Link to post
Share on other sites

George put an easy reach air-fuel mixture screw on mine, makes it easy to fiddle with.

When the bike is reluctant to spin over Ive found that both one single kick, and the ebutton at the same time gets it spinning. Probably a good strategy for dead start races as well.

Personally i wish the carb had a hot start button.

We are lucky to have George from Uptite on here!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×