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Discussion Starter · #1 ·
Bike is in the shop now getting 95" jugs, Weisco flat top pistons, Andrews 37G cams, Ported heads done by the shop. The guy who owns the shop says he's not sure yet but might stick with the stock 40mm carb but wants to look into it. He also said I don't need the 6200rpm ignition . I checked with Andrews and they said the 40mm carb might be to small and I might not be sufficient at higher rpm's and the 44mm would be better. I keep getting conflicting recommendations on the carb size. Also if I'm never gona shift at 6200 why would I want the high performance ignition? Most of the 37G dyno sheets I've looked at drop off after 5000 or so rpm anyway.
I know I have two separate questions here but I'm starting to get confused. The guy who owns the shop has a great rep so should I just let him do what he thinks is best and stop making myself CRAZY.
 

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IronButt
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There is a saying " you have to give something to get something"

If you use the 40 cv in fact yes you may give up some top end power, but low end throttle response and tq will be better. Head porting will play apart, comp ratio, pipes and so on . The 44 works very well and I doubt that you could feel the difference a dyno would show it but you would feel the difference on the top end with 44cv. The cv is a very forgiving carb by design, if you have teh cash go for it and upgrade later. I like to use the 44 for a hot 95 and the 98 really like it. These engines are nothing more than air pumps. Hope I was of some help
 

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Discussion Starter · #3 ·
Yes, HDWRENCH, that was very helpful and the guy from Andrews said the same thing about low end throttle response. When you said I would feel the difference at higher rpm, do you mean I would have more acceleration at higher rpms with the 44mm . Also do you agree with not needing the perf ignition ?
 

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Discussion Starter · #4 ·
You were right HDWRENCH. The bike pulls great till about 4800-5000rpm and then seems to peter out. I'm gona have it dynoed soon and see what they say. I raced a guy with the same build except he has an injected bike and his revs to 6000 plus rpm. He startd to pull away quite rapidly when we hit about 85mph. Otherwise we were pretty even until then.
 

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I have that build with EFI and ported TB and the 85mph you were talking about, well, that's where the fun really starts!!! Mine is accelerating so hard and fast at that speed under racing conditions(simulated of course;) ) it is awesome. I don't know about engines or carbs or efi but if you're not pulling like a outta control freight train at 85mph, sounds like you need that carb...
and some dyno time....
OBTW, I know what my dyno says but will tell you under riding conditions, I take mine out past the 5500 frequently and it's still pulling great. I haven't hit the rev limiter (6200) yet but get to 6k occasionally. I have about 700miles on my build so far and absolutely love it! It is still pulling so hard at 100+ it's amazing!
Was riding with my main riding buddy for the first time since my build the other day, he has a stock Deuce and his bike was always just a short hair faster than my Road Glide...
So we hit this spot where we like to run em(race) out and I'm riding 2-up we're running about 60 and I roll on, not even that hard, and just start walking away from him, figured he didn't try to go with me I left him so fast. We get up to the stop and he gets off his bike and he's walking around my bike and looking at it and using a few expletives, I ask why he didn't go with me and he exclaims I DID!! FU*k! FU*k! FU*K! he says I gotta get me one of those! I guess you had to be there but it was very funny! Men the OL wer laughing our asses off, he's not a very demonstrative type person.... I laughing now just remembering it...
 

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Livin' Free Indeed
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I've basicly got the same set-up as you plan to go with courtesy of Mr. HDwrench. I went with the SE 44mm CV carb & also Dewey's pro-street heads. I'm just getting going at around 80 mph, after that it starts to get scary fast. I don't race stop light to stop light (well, sometimes). I do ride the freeways a lot & like being able to get up & go when I'm already doing 80mph to pass someone.

Head work has a lot to do with performance. Also the 6200 SE igniton also advances timing 5 degrees which is good. I don't quite know why, I've been told. Any one care to elaborate on timing theory?

I'm running V&H Bigshots that I do notice give me a bit of a torque dip at around 2500 rpm, but after that torque starts cranking right up. HP doesn't start to fall off til aroung 6000 rmp if my memory is correct.
 

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Discussion Starter · #7 ·
I'm going to talk to my mechanic tomorrow and go for the 44mm. Seems to me I should just put it on before I have it dynoed other wise I'm just going to have to dyno it twice. Might as well go for the 6200rpm ignition also!
 

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reg26 said:
You were right HDWRENCH. The bike pulls great till about 4800-5000rpm and then seems to peter out. I'm gona have it dynoed soon and see what they say. I raced a guy with the same build except he has an injected bike and his revs to 6000 plus rpm. He startd to pull away quite rapidly when we hit about 85mph. Otherwise we were pretty even until then.
Yeah, you just have to ask yourself which is more important, top end power or low to mid range (streetable) torque? How often are you going to be riding at 5000+ rpm? It's hard to get both top and bottom end torque. A programmable ignition module would help a lot, too.
 

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Discussion Starter · #9 ·
True Todd, but I wont loose what low and mid range I have I'll just pick up some more on the top end where it starts to peter out.
 

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reg26 said:
True Todd, but I wont loose what low and mid range I have I'll just pick up some more on the top end where it starts to peter out.
Yes, you may be right... Still, I can't imagine why it's "petering out" at such a low speed. That carb should be plenty for that engine. Hell, a basic S&S Super E will handle a 95 inch engine with no trouble, so a 40 mm CV should be plenty big enough for your engine.

If I were you, I would put it on the dyno first before you go spending a lot of money on something you might not need. Of course, if you have the cash to burn, then go for it. Remember, there are a lot of shops out there (especially dealerships) that just want to make a buck selling you unnecessary parts when you don't really need them. It sounds to me that you might just need to get it tuned properly. If that doesn't help, then get the new carb. That's my 2 cents.... Good luck! {salute(
 

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Discussion Starter · #11 ·
Thanks for the info Todd but the shop that installed it is the one who told me to hold off on the 44mm. He said I might not need it and I might loose some on the top end, which I feel I am. So I don't think he just wants to sell me some more parts. I have a friend with the same build but he has a 44mm and at about 85 or so mph he starts to pass me other wise we are about the same to that point. When I asked Andrews what carb to use they suggested the 44mm also for just the same reason. The shop I used is known for good tuning of carbs and the has won many a national drag race. I'm pretty sure he has it tuned well. So I figured instead of spending the money on a dyno just to find out what I think I already know would be a waste of money. I've already had Andrews, HDWRENCH and other forum members tell me there experiance and opinions so I feel confident about going with the 44mm. Then I will have it dynoed and let ya know.
 

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reg26 said:
Thanks for the info Todd but the shop that installed it is the one who told me to hold off on the 44mm. He said I might not need it and I might loose some on the top end, which I feel I am. So I don't think he just wants to sell me some more parts. I have a friend with the same build but he has a 44mm and at about 85 or so mph he starts to pass me other wise we are about the same to that point. When I asked Andrews what carb to use they suggested the 44mm also for just the same reason. The shop I used is known for good tuning of carbs and the has won many a national drag race. I'm pretty sure he has it tuned well. So I figured instead of spending the money on a dyno just to find out what I think I already know would be a waste of money. I've already had Andrews, HDWRENCH and other forum members tell me there experiance and opinions so I feel confident about going with the 44mm. Then I will have it dynoed and let ya know.
Great! As long as you're sure that the carb is the problem, go for it! I was just trying to help you determine the exact cause before spending your hard-earned cash. It sounds like you've done your homework. ;) Enjoy!
 

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Todd
You would be better served to be sure you have pipes that match the buld and will optimze power and torque. Eyes on the wrong part IMO.
 

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Discussion Starter · #14 ·
Thanks Todd. Thats why I like this forum people make you think things thru so your chances of doing something wrong are minimized.
 

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nw_guy4_fun said:
Todd
You would be better served to be sure you have pipes that match the buld and will optimze power and torque. Eyes on the wrong part IMO.
I agree about the pipes. They make a huge difference in overall performance, even more so than the carb. I've tried many exhausts and have now settled on the V&H Pro-Pipe as my exhaust of choice for any size engine.

As for the carb, I was simply noting that I've seen large engines running 40 mm carbs and they didn't have any problems. That could have just been due to the rider's individual riding style, though. :) You have to have all the parts correctly matched and working well together. A lot of people "over carb" and "over cam" an engine and have to change several other things in order to make it work.... i.e. putting an 850 cfm carb on a slightly modified chevy 350. I've seen it done and it ran like crap at low speed.
 

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adlerx said:
OBTW, I know what my dyno says but will tell you under riding conditions, I take mine out past the 5500 frequently and it's still pulling great. I haven't hit the rev limiter (6200) yet but get to 6k occasionally. I have about 700miles on my build so far and absolutely love it! It is still pulling so hard at 100+ it's amazing!
You are running that hard with only 700 miles on the build? Ouch! Hope ya don't cause any damage to it! It's not advisable to even do a full power run on a dyno until AT LEAST 1500 miles. The parts haven't begun to settle in yet until after that time, so the engine won't even be making all the power it could be making. 1500 miles is not a long time to wait in order to get it broken in properly... you can do it in a week, just taking it easy.
 

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Discussion Starter · #17 ·
There's a shop here on the island that is very well known who has done a few of my friends bikes and he puts em on the dyno right after completing the work. When you pick your bike up he tells you that no break in is necessary and just ti ride it normally. The people I know who have used him have not had any problems at all in thousands of miles. I didn't use him for my own reasons but the shop that did mine gave me instructions as to how to break mine in and told my I shouldn't have it dynoed till I have a thousand miles on it. I don't know why both systems seem to work but I definitely feel better having given mine a break in period.
 

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ToddM said:
You are running that hard with only 700 miles on the build? Ouch! Hope ya don't cause any damage to it! It's not advisable to even do a full power run on a dyno until AT LEAST 1500 miles. The parts haven't begun to settle in yet until after that time, so the engine won't even be making all the power it could be making. 1500 miles is not a long time to wait in order to get it broken in properly... you can do it in a week, just taking it easy.
Actually, I had my build broken-in on the dyno using a procedure that has been well documented to produce much better results than "old-time" methods. I did take it pretty easy for the first couple of hundred miles. And just so we're clear on this, I am not running it hard! It does all this so easily, I have only used WOT once or twice tops. With all that power, it simply doesn't require "running hard" to really give a thrill.
I have all the confidence in the world in the break-in procedure used. Alot has been discussed here regarding break-in procedures recently.
In my opinin, a 1500 mile break-in is just plain silly! Never heard of such a thing!
OBTW, Have you seen my dyno sheet?
 

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The dealer I use breaks them in on the dyno, then they wind her up and do the tuning. It's ready when you pick it up.
 

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adlerx said:
Actually, I had my build broken-in on the dyno using a procedure that has been well documented to produce much better results than "old-time" methods. I did take it pretty easy for the first couple of hundred miles. And just so we're clear on this, I am not running it hard! It does all this so easily, I have only used WOT once or twice tops. With all that power, it simply doesn't require "running hard" to really give a thrill.
I have all the confidence in the world in the break-in procedure used. Alot has been discussed here regarding break-in procedures recently.
In my opinin, a 1500 mile break-in is just plain silly! Never heard of such a thing!
OBTW, Have you seen my dyno sheet?
That's good. There's nothing wrong with doing it that way. I made the comment because you didn't mention that in your first post. :) I've seen more than a few people rush the break-in process and and end up doing damage to their engine. I guess that if you don't do your own work, it's better to let the builder break it in. Only they can tell if something is wrong during the run. I always build my own engines, so I suppose I wouldn't trust someone without any experience to break it in, either.

Maybe I'm just too used to doing it the "old fashoned" way... Been doing it that way for over 25 years and haven't had any problems. I don't always have the money to pay for a total dyno break-in run.... I'd rather spend that money on performance goodies. :D I get mine dyno-tuned every spring and it only costs me 50 bucks. A total break-in run would cost me a LOT more! I don't mind taking it easy doing a break-in on the road... 1500 miles isn't much at all and only takes me a couple days to accomplish. That way, I can "feel" the engine as it breaks in. Besides, I'd rather be riding the bike than watching someone run it on the machine all afternoon. :) I can't believe that you've never heard of a 1500 mile break-in!!!?? It's a tried and true method that's been used for almost 100 years, so I wouldn't exactly call that "silly"! :)

I'm just not so impatient that I need results right now. ;) I guess that's just a result of today's fast-paced world... everyone want immediate results. There's no reason to rush things, IMHO. The old adage "good things take time" is true. But, if it works for you... do it and have fun! :D :cheers:

Oh yeah... I haven't seen the sheet, but judging by the parts you've used, I'm sure it's cranking out some nice torque. Still, I'm sure that your engine will still be creating more and more power the closer you get to 1500 miles. Parts only wear in at a specific rate, depending on engine speed, oil condition, heating/cooling cycles, etc., so whether it's considered "broken in" or not, everything is still wearing and seating at this point. Only time will completely seat all the parts.
 
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