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98" big bore

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Old Mar 7, 2017 | 05:58 PM
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Default 98" big bore
Scott from hillside cycles done a awesome job on everything I needed for my big bore kit with his stage 1 heads. I already had andrews 26 cams and a dragos dragula 2 2/1 exhaust. I had it dynoed at ray price in Raleigh Nc. The bike runs great but every now and then on cold start up I get a back fire. I kinda feel like it's running a little rich. Here is my dyno sheet. Do you think a new tune from somewhere else get more out of it then this and any idea on the backfire.
 
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Old Mar 7, 2017 | 06:06 PM
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Quite the dip in the torque curve.
I would bring it back to the guy that did the tune and ask him to fix your backfire issue. He should back his work.
 
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Old Mar 7, 2017 | 06:24 PM
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Any idea on the dip in the torque curve
 
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Old Mar 7, 2017 | 06:34 PM
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Do you have any baffles in the pipe?
 
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Old Mar 7, 2017 | 06:36 PM
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Yes have 2.5" baffles
 
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Old Mar 7, 2017 | 06:43 PM
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A backfire when cold is usually a lean issue. Check to make sure you don't have an exhaust leak at the head where the pipe goes in. That could cause your backfire issue, too.
 
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Old Mar 7, 2017 | 06:45 PM
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I'll check that. Thanks for the info
 
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Old Mar 7, 2017 | 06:47 PM
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Sure. I'm no expert on this stuff.
Others in here know far more than me.
The numbers look ok for that cam actually, but that dip is unusual for a 26 since it is pretty much a lower end cam.
 
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Old Mar 7, 2017 | 06:51 PM
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here is a link to another thread on your pipe. Maybe this will help you figure your issue out.
https://www.google.com/url?sa=t&rct=...npePPzgQKJzgIw
 
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Old Mar 7, 2017 | 07:06 PM
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Thanks for the link I have the 2.55 baffles not the 2.50. Somethings going on just need opinions.
 
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