Backfire during deceleration

Message

TG2891 · #1 Post by **TG2891** » Fri May 25, 2007 12:59 am

I bought a 2nd c-dale (Blaze) and finished getting it back in running condition but I am having a few issues getting it to run properly.

I just put the motor back in, set the throttle and loaded a blaze map provided on the disk I got when I bought my D&M Kit. (I used the same map in my speed and other than leaning it out to stop fouling plugs I have had no ill running effects in the speed.)

But when I loaded it in the Blaze I am getting a backfire when I decelerate. Also if you look down the exhaust pipe while the bike is running you can actually see the exhaust glowing. I am guessing that it is running to lean, But would that cause the backfire?

The setting running in it now are: .8 offset, 2550 flow rate and .5 TB leakage.

What is the TB leakage and what are the effects if it is changed up or down?

Lastly, I read somewhere in this forum that by loading a map that lowers your rev limit, you greatly reduce the risk of stock crank bearing failure. Is this true and does anyone have such a map?
This is a stock motor with less than 15 hours on it and I am not looking to ruin it before I get a chance to tear it down this winter and put in a new crank bearing.

I don't know if this info will help with the selecting of a map but: The bike will see 90% woods riding so high speed and alot of top end is not needed.

Thanks
Tom
540-834-9336

jesshamner · #2 Post by **jesshamner** » Fri May 25, 2007 2:33 am

What is the VIN?

cannondale27 · #3 Post by **cannondale27** » Fri May 25, 2007 12:10 pm

QUOTE (TG2891 @ May 24 2007, 07:59 PM) <{POST_SNAPBACK}>

I bought a 2nd c-dale (Blaze) and finished getting it back in running condition but I am having a few issues getting it to run properly.

I just put the motor back in, set the throttle and loaded a blaze map provided on the disk I got when I bought my D&M Kit. (I used the same map in my speed and other than leaning it out to stop fouling plugs I have had no ill running effects in the speed.)

But when I loaded it in the Blaze I am getting a backfire when I decelerate. Also if you look down the exhaust pipe while the bike is running you can actually see the exhaust glowing. I am guessing that it is running to lean, But would that cause the backfire?Yes it could

The setting running in it now are: .8 offset, 2550 flow rate and .5 TB leakage.
Looks like Jesshammer is getting your stock settings.Thats a good start.Does your speed have stock exhaust.That may be reason it is not running lean
What is the TB leakage and what are the effects if it is changed up or down?
Just what it says.Some throttle plates dont fit perfectly so a offset is used to make it easy to compensate

Lastly, I read somewhere in this forum that by loading a map that lowers your rev limit, you greatly reduce the risk of stock crank bearing failure. Is this true and does anyone have such a map? It cant hurt longevity.Do you want a Blaze map with what revlimiter
This is a stock motor with less than 15 hours on it and I am not looking to ruin it before I get a chance to tear it down this winter and put in a new crank bearing.

I don't know if this info will help with the selecting of a map but: The bike will see 90% woods riding so high speed and alot of top end is not needed.

Thanks
Tom
540-834-9336

TG2891 · #4 Post by **TG2891** » Fri May 25, 2007 1:12 pm

1st - here are the VIN#'s

Blaze
Motor - AAA5B3000220
Frame - 5B6DB362B000076

I bought both of these quads from the same guy, the speed first and then the blaze. I was told that he swapped the motors prior to me buying the speed and then it turn out that one of the stage 8 bolts came loose in the motor he put in the blaze and thrashed the pump gears. So now I have it too. The point of all this is: I am not sure if the orginal VIN #'s are needed for the info you are looking for. So here are the numbers for my speed.

Speed
Motor - AAA5B2001215
Frame - 5B6CD31G53B000015

2nd - The speed does have the stock exhaust. Light in my head just came on, free flow exhaust & less exhaust back pressure = less resistance, free flow, better performance, better fuel burn = leaner exhaust gas & Hotter exhaust. Sometimes you got to smack me upside the head to get my brain to think. I will richen the fuel mixture and cool it down. Thanks

3rd - Well the question is: How do you determine how to set the TB leakage rate? And can that effect the throttle flux while at idle? Both motors idle flux between 100-150 rpm. Or is this normal? I thought it was so I never trierd to do anything about it.

4th - I would like to try the lower rev map if you have one. If you want to send more than one I will try those too. What is the limit set at? I read somewhere that the stock limit is set at 11800 but the stock bearings in the crank are only tollerant of around 10500. Something to do with them designed to be used in a grease not a oil bath.

Thanks for reading
Tom
540- 834-9336

jesshamner · #5 Post by **jesshamner** » Fri May 25, 2007 3:02 pm

Blaze
Motor - AAA5B3000220
Frame - 5B6DB362B000076

Are you sure about the VIN? The only thing close that I could find was an 02 Blaze; 5b6db31362b000076.

jesshamner · #6 Post by **jesshamner** » Fri May 25, 2007 3:10 pm

VIN
5b6cd31g53b000015

INJ FR
2400

OFF
1.1

AFR
12.1

jesshamner · #7 Post by **jesshamner** » Fri May 25, 2007 3:20 pm

So he swapped the speed and blaze motors? And now you have a speed with the blaze motor and a blaze with the speed motor?

TG2891 · #8 Post by **TG2891** » Fri May 25, 2007 5:26 pm

Yes, he swapped the motors before he sold the first one to me. Is there much of a differance? Should I swap them back to the orginal frame? I know that the orginal Blaze motor is a unicorn and the orginal Speed motor is not.

jesshamner · #9 Post by **jesshamner** » Sat May 26, 2007 1:58 am

Well if the speed motor is in the blaze, you now have original injector cals. Put those in and start from there. If you still have the blaze exhaust, you will probably be a little lean. Fatten it up a little and you should be good to go.

TG2891 · #10 Post by **TG2891** » Sun May 27, 2007 2:37 pm

Thanks for the help. I will let you know how it goes.

Tom