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Discussion Starter · #1 ·
....
 

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Discussion Starter · #3 ·
Yeah I know. I was hesitant to do a non reversible change like this, but I've read about so many Bolt owners that have done the simple 1.5" hole saw modification that I figured why not. Worse case it will give me a reason to cough up for an aftermarket exhaust. It's a little bit louder at idle but the weather has kept me from road testing it. Probably do that tomorrow or maybe this evening. I'll let you know.
 
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Discussion Starter · #4 ·
Uh oh! Schu? What did you go and did?!馃 How does it sound?! Better or worse? Obnoxiously loud? I've had the drill with the hole saw chucked up a couple of times, but couldn't do it. Maybe now......
Just rode about 20 miles. The hole saw accomplished exactly what I wanted. It has a ballsier sound at idle but it really isn't any louder. My sound meter phone app registered the same 83db at idle before and after I drilled it out. Revving it up off idle doesn't sound much different but it does has a slight pop and gurgle that you get with most free flowing exhausts when you back down. On the road it sounds ballsier under acceleration but it sounds nearly the same when running at speed. The most noticeable change in sound is when you are down low in rpms and lug it up to speed from a tall gear instead of downshifting. Has a real nice sound thru that range. So to summarize all that.....it sounds better at idle and when you let the Vtwins low end torque pull it up from nearly chugging. Outside of that it didn't really change much.
 
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Discussion Starter · #5 · (Edited)
UPDATE:
Ok now that I've logged over 100 miles on the modified exhaust I am being told that although it might not seem much louder in the saddle, it is noticeably louder to the passerby or those you are riding with. But all comments have been favorable and are typically followed by the commenter helping themselves to my throttle and revving it up with a smile on their face.

Bottom line.......I like it a lot!
 

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UPDATE:
Ok now that I've logged over 100 miles on the modified exhaust I am being told that although it might not seem much louder in the saddle, it is noticeably louder to the passerby or those you are riding with. But all comments have been favorable and are typically followed by the commenter helping themselves to my throttle and revving it up with a smile on their face.

Bottom line.......I like it a lot!
Is that the Two Bros pipe out the window now then??!
Ben
 

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Discussion Starter · #7 ·
Is that the Two Bros pipe out the window now then??!
Ben
Yeah I don't know that I could get myself to drop that kind of money on pipes when they really don't make that much of a difference in performance. Now It sounds better, but still looks odd. There just isn't anything you can do about the look of the stock exhaust other than replace it. My next upgrade will be Ivan's reflash.
 
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Discussion Starter · #8 · (Edited)
I've had the drill with the hole saw chucked up a couple of times, but couldn't do it. Maybe now......

@[email protected]
Do it Jay. I have just over 200 miles on the opened up exhaust. Best 5-minute modification I've ever done. You will like it. Trust Me!
1.5" bi-metal holesaw with 12" extension.
 

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I've had the drill with the hole saw chucked up a couple of times, but couldn't do it. Maybe now......
@[email protected]
Do it Jay. I have just over 200 miles on the opened up exhaust. Best 5-minute modification I've ever done. You will like it. Trust Me!
1.5" bi-metal holesaw with 12" extension.
Ugh! The peer pressure! Fine, I'm gonna do it. I'll let you know when I get er done.
I do have one concern though...
Having changed out the air cleaner, thus leaning out the fuel/air setting.
I can only imagine that drilling out the baffle will lean it out even more.
I really don't want to remap or reflash or install a Power Commander.
What do you think about that?!馃
 

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Discussion Starter · #10 ·
Ugh! The peer pressure! Fine, I'm gonna do it. I'll let you know when I get er done.
I do have one concern though...
Having changed out the air cleaner, thus leaning out the fuel/air setting.
I can only imagine that drilling out the baffle will lean it out even more.
I really don't want to remap or reflash or install a Power Commander.
What do you think about that?!馃
Then don't do it Jay. Seriously. If you are worried about that.
I gotta believe there is some leeway, but I do plan on getting an Ivan reflash in a couple months based on my K&N and a 2 Bro's exhaust. (Someday)
 

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Ugh! The peer pressure! Fine, I'm gonna do it. I'll let you know when I get er done.
I do have one concern though...
Having changed out the air cleaner, thus leaning out the fuel/air setting.
I can only imagine that drilling out the baffle will lean it out even more.
I really don't want to remap or reflash or install a Power Commander.
What do you think about that?!馃
Then don't do it Jay. Seriously. If you are worried about that.
I gotta believe there is some leeway, but I do plan on getting an Ivan reflash in a couple months based on my K&N and a 2 Bro's exhaust. (Someday)
I pulled out a spark plug and took a look at how the engine was running at the1,000 mile mark. It looked pretty lean, but I had nothing to compare to. I'm going to have another look soon at the 4,000 mile mark. I guess I'm a little worried about running too lean and possibly burning a valve? I hammer on the poor girl and still get 54 mpg! I think that I would feel better if I got a lower mpg reading! I'd rather put the money in the gas tank than into the engine for repairs! I will post pics of the plugs when I can. Cheers!
 

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Discussion Starter · #12 · (Edited)
Compare Plug (too lean?)

I pulled out a spark plug and took a look at how the engine was running at the 1,000 mile mark. It looked pretty lean, but I had nothing to compare to. I'm going to have another look soon at the 4,000 mile mark. I will post pics of the plugs when I can. Cheers!
Here is my forward cyl plug after 3,500 miles. The trailing cyl looks almost impossible to pull the plug without at least raising the rear of the tank. I have the stock ECU with no changes to the air-fuel settings. All of these miles were with the K&N intake and the last 200 miles with the exhaust opened via 1.5" hole thru the first baffle plate you come against when entering your bit from the rear. (That description will bring out the comments)

This plug looks sooo lean to me, but I'm used to changing plugs on 2-strokes which are usually dark and wet. The plug was checked immediately following a good 95 mile ride with most of it at 50 to 60 MPH right up to my driveway. I know the old school method on 2-strokes was to run flat out and kill the ignition, coast to a stop and burn your fingers to get an accurate plug read. I didn't do that method.

I am interested in seeing the comparison of this plug to your plug being similar mileage. Also interested in the opinions of others if willing.
 

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Discussion Starter · #13 · (Edited)
Few more not so close up.
Also plug chart found online.
I think I am on the lean side of OK.
 

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I just know to be looking for a light tan brown colour. Your first set of pictures look ok to me - the second set make it look a little whiter (i.e. leaner), but then the 2nd pics overall are a little lighter, so could just be the effect of your flash.

Having said that, a quick google of a couple of random bike forums suggest EFI bikes tend to run leaner/hotter, so the plugs therefore tend to err towards the greyer end of the scale. Probably makes sense given the push for efficiency nowadays, and the resultant hotter running conditions of modern (esp air cooled) bike engines. Some suggestion the more tanned colour of plug is more relevant to carb鈥檈d bikes.

Ben
 

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I just know to be looking for a light tan brown colour. Your first set of pictures look ok to me - the second set make it look a little whiter (i.e. leaner), but then the 2nd pics overall are a little lighter, so could just be the effect of your flash.

Having said that, a quick google of a couple of random bike forums suggest EFI bikes tend to run leaner/hotter, so the plugs therefore tend to err towards the greyer end of the scale. Probably makes sense given the push for efficiency nowadays, and the resultant hotter running conditions of modern (esp air cooled) bike engines. Some suggestion the more tanned colour of plug is more relevant to carb鈥檈d bikes.

Ben
My stock plugs didn't look much different with zero changes. I'm with the f.i. running cleaner theory. Your plugs have a bit of chemical deposits on the electrodes from whatever additives they put in pump gas. Lean lean would burn that away, wouldn't it?
I wish we had an easy way of measuring cyl. head temperature like on an aircraft engine.
 

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Discussion Starter · #17 ·
For what it's worth, this is a plug out of my girlfriend's completely stock V-Star 950 after maybe 6-7k miles.
It's a CPR7EA-9, too.
Thanks @eddie and @SCRBen for the feedback. @[email protected] started making me nervous........
Now I can put that one behind me and worry about something else.
 
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Thanks @eddie and @SCRBen for the feedback. @[email protected] started making me nervous........
Now I can put that one behind me and worry about something else.
How long did it take to pull the front plug, out of interest? I鈥檝e not even tried yet, but they do look to be well-recessed in there.
Ben
 

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Thanks @eddie and @SCRBen for the feedback. @[email protected] started making me nervous........
Now I can put that one behind me and worry about something else.
How long did it take to pull the front plug, out of interest? I鈥檝e not even tried yet, but they do look to be well-recessed in there.
Ben
The front plug comes right out with a long extension. The rear one looks pretty accessible, especially if you remove the seat.
 

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Discussion Starter · #20 ·
How long did it take to pull the front plug, out of interest? I鈥檝e not even tried yet, but they do look to be well-recessed in there.
Ben
The front plug only took a few minutes to pull. Most of it spent trying to fish it out of the well after it slipped out of the socket. I lined the socket with plastic cut from a ziploc bag to hold the plug inside the socket as I lowered back down the well. I didn't even try the rear plug yet.......
 
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