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Where to set the rev limit?
- hardr0ck68
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- Who put the what in the where?
That number sounds high to me considering what was discussed in other threads about max RPM's. I wonder if the guy I was talking to factored in oil flow and bearing limits before giving me sugh a high number...
I am afraid with the lighter crank, clutch, and rods the motor will rev up quickly, so a rev limiter seems like a good peice of kit for insurance. The top end will be mostly stock kz750 parts.
So does anyone have a good idea as to what would be a safe limit?
Am I correct to think that it SHOULD be valve float that will cause engine failure first at high RPM?
If valve float is the key factor is there a formula to calculate when the valves will float (figuring in spring tension, valve weight and rpm)?
Thanks for any input.
1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- kaw-62046
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- will61310
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...1980 LTD 1000...
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- timebomb33
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1973 z1 2-1974z1-a,2-1975z1-b dragbikes1015cc+1393cc, 1977kz1000,1978kz1000,1981kz1000j, 1997 zx-11, 2000 z12r,1428turbo nitrous pro-mod and a shit load of parts thats all for now leader sask.,CANADA
I THINK MY POWERBAND BROKE
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- Becker
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- The Doctor Will Rise Again
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78 KZ750B3
79 KZ400 LTD
78 KZ650C2
79 KZ650C3
78 KZ650B2A
80 KZ650F1
80 KZ650E1
81 CB750K Super Sport
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- mark1122
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- Keep twisting it
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If u put in stronger springs u can raise that.
And as timebomb said , when it stops making power stop reving.
So then u look at what stops it from making power, fix that and u can rev higher. always keeping in mind the mechanical limits of course.
1 thing that commonly stops it from making power, is its ability to breath. so then u need to analyze that. the usual things are small parts. ports, valves, cams, carbs.
Keep in mind that as all of these things grow, your torque curve goes up with them. so now u have a motor that will scream at the top rpms :woohoo: , but lacks that beautiful torque on the bottom.
76 KZ, frame gusset work,1200CC.Ported by Larry Cavanaugh, 1.5mm.over intakes, Carron Pipe, ZRX12 rear end, and seat,96zx9 front end.
01 CBR600F4i Track bike.
Cobourg, Ont. Can.
~ ~ ~_@
~ ~ _- \,
~ (k) / (z)
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- hardr0ck68
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I will need to buy some dyno time, it will be good to make sure my air/fuel gauge matches the dyno's sensor and to tune the bs32's I will be going with. It is unfortunate that I will need to re-do everything on a dyno in another year when I have the funds/time to tackle the top end. But at least my project is more than a worn out picture of an empty frame.
So until I get to a dyno 11K RPM would be a good start?
1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- keith1
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and it goes on........:S
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- timebomb33
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1973 z1 2-1974z1-a,2-1975z1-b dragbikes1015cc+1393cc, 1977kz1000,1978kz1000,1981kz1000j, 1997 zx-11, 2000 z12r,1428turbo nitrous pro-mod and a shit load of parts thats all for now leader sask.,CANADA
I THINK MY POWERBAND BROKE
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- hardr0ck68
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I had not planned to touch the head this winter (cause if I start replacing valve guides, well then I will need to have the seats cut, and hell oversized valves are only a few hundred bucks so I should go ahead and add those while I need to get the seats cut anyway, then you of course a cam to make them work "right" oh hell; and some light porting to blend the new seats in.... )
I know when it is time to do the head I will spend at least 1K on it.... but until then I am just going to use a stock gpz750 head with stock springs (I will test the spring tension as per the FSM's instructions).
1977 kz650 c1
bought it because I was told it would never run again...I like to prove people wrong.
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- timebomb33
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1973 z1 2-1974z1-a,2-1975z1-b dragbikes1015cc+1393cc, 1977kz1000,1978kz1000,1981kz1000j, 1997 zx-11, 2000 z12r,1428turbo nitrous pro-mod and a shit load of parts thats all for now leader sask.,CANADA
I THINK MY POWERBAND BROKE
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- will61310
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But at least my project is more than a worn out picture of an empty frame.
and it goes on........:S
Insert picture of dead horse.......Here :laugh:
...1980 LTD 1000...
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