Need some help guys. My bike stalls while downshifting mostly from second to first but occassionally when I downshift from third to second. It doesn't happen all the time but often enough for me to be concerned. I'm wondering if it has anything to do with the pc3.... the bike also started to back fire a little when i down shift. any help is greatly appreciated thanks

 

what kind of bike and have you set the IDLE to spec ? Any mods or is the bike ALL STOCK ? How long have you been riding ?
Alot of the time it is a NEWER RIDER not being smooth.

 

I have been riding for about 8 years now... I have a 05 636 w/ a yoshi rs5 exhaust, pc3, and bmc filter. The idle is set to spec. When I downshift to first my rpms drop down real low and the bike stalls out. I'm goonna hook up the lap top to the bike tomorrow to see if it has anything to do with the pc3, but I doubt it. I've had the pc3 on the bike for about a month now and the problem just started a couple of days ago. Like I said it doesn't happen every time, but often enough.

 

I think it was TX that had a similar prob once before... Ended up being his throttle bodies.... With the backfiring starting to happen, and the bike cutting out, I would have to guess the PC3...... With the bike popping, sounds like a fuel prob...

An intake leak or a vacuum leak somewhere, it could cause a very similar problem also....Easy enough to check the PC tho', and maybe go from there....

 

Also there is little need for down shifting 2nd to 1st or 3rd to 2nd. IMO use your brakes, why put the added strain on the motor and trans if you are just stopping. 50.00 brakes or 500.00 trans. JMO though.

BTW Sup my KF bros and sisters! Glad to be home.

 

I was told by powercommander that the PCIII doesnt control idle...so i doubt it is that. sounds like your throttle bodies are going out.

 

You have a long way to go . Proper down shiftng DOES NOT DAMAGE YOUR TRANY . Engine breaking is very important to prevent overloading a tire by using the brakes in certain circumstances . You Rev the bike to 10 grand . So why IYO is the engine reving
without throttle bad . If you were to say that to the pros I hope one of them would take the time to EXPLAIN the importance of Down Shifting and engine breaking to you .

 

When entering a corner I prefer to get to my entry speed by braking downshifting to the appropriate gear and then turn in with out unneeded downshifting that will most likely unsettle the suspension and also takes longer.

Consider this;
1 is it faster to down shift your way to your entry speed
2 apply brakes and select proper gear for your turn when at the correct entry speed.
If you are choosing #1 you may want to rethink it.

You want to ask a pro, do you see them every Sunday downshifting gear by gear into the corners, no. They use # 2.

I am no pro and as far as street ridding is concerned if you feel the need to downshift between every light then go for it. I will continue to use my brakes, thank you.

 

On topic: It sounds like a vaccum leak. Check all of your hoses. This would cause the engine to run rich and lead to backfiring.

Off topic:
The only reason why professional racers used to not downshift into corners is because the dramatic slowing of the rear tire at low rpms and high speed would cause the rear tire to get loose and wear the tire very quickly and could cause loss of control. Nowadays with Slipper Clutches like those on our new 636's, there is no worry of overeving the rear tire as they downshift going into corners. This keeps them in the right gear and keeps the rpm's up in the torque curve. I can see this as being tough on the clutch since it gets more use but it will not harm the tranny. It's pretty impossible to grenade a motorcycle tranny unless you are trying to put 200+hp through it.

I downshift everytime unless I am coming to a stop, then it is unessecary.

 

Completely Off Topic:
I always downshift, but try not to use engine braking for any sort of aggressive braking. Gentile slowing, sure... roll off, and/or downshift, but otherwise I do my best to keep my engine speed and road speed lined up... and be in the right gear. I don't have a slipper clutch... But even if I'm coming to a stop, I like to be in the right gear in case I need to get going again in a hurry...