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Turning Wrenches / Re: RD transmission questions on hp
« Last post by dvsrd on Today at 12:37:54 AM »
So, I have has this fairly out-there project in mind for a decent amount of time.
It involves the use a stand-alone motor crank case and a separately bolted on transmission assembly.

The engine will produce 150 hp at the crank. And this particular engine is the center of the project..

Now, what is the hp capabilities of an RD transmission and clutch assembly?
Id like to use the RD stuff simply because I've got lots of them here and I've also got cases to use as well.

This engine/transmission assembly will find its way into an RD 400.
Since you will have a separate transmission anyway, I would have looked into various Harley big twin gearboxes. They will stand up to the torque, since your 150 bhp (snowmobile 800 cc twin?) will be at much higher revs than any HD, so torque will be pretty much the same. That would also allow use of a primary belt, that would simplify things. Alternatively a Norton Commando gear box, which would have a slimmer clutch/ primary cover than a HD one. In both cases, custom/racing gear sets are available, up to 6 speed. (Baker, Nova, etc) None of these alternatives will be cheap, and you most likely will end up with something too big (long) to fit a 400 frame anyway.

An even more expensive alternative would be the box internals from some modern 1000 cc superbike with vertically stacked shafts, inside a custom housing.....
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Turning Wrenches / Re: RD transmission questions on hp
« Last post by Seizer on Today at 12:05:35 AM »
150 HP in an RD frame? Yikes.
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Turning Wrenches / Re: Keihin PWK jetting
« Last post by dvsrd on Yesterday at 11:38:01 PM »
JJH, but it's not breaking up coming on the main , it's after the throttle has been wide open .. which I guess needle taper could affect ??
I have no experience with PWK carbs, but I'll take the risk and throw out a couple of suggestions for basics to check anyway:

Needle jet size? If the needle jet is too small, main jets or needles do not really change things that much. I once read that you could check if the needle jet is large enough by removing the main jet (or use one that surely is too large), and do a test run. If it clearly runs too rich (4 strokes) after 3/4 throttle, then the needle jet is definitely large enough.

Float valve size? Is your float valve large enough. And obviously the float level needs to be correct as well.

And fuel supply? As in petcock, tank vent etc. If you can remove the float chamber plugs, and somehow collect the fuel flowing out, you can check if the fuel flow is sufficient. A rule of thumb is bhpx13= ml/min.  So if we assume 45 bhp, your fuel system needs to flow at least 585 ml/min. (or about 21 fl. oz )

Good luck!
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Turning Wrenches / Re: RD transmission questions on hp
« Last post by sav0r on Yesterday at 09:24:48 PM »
Iíve asked a similar question many times, but the truth is that the RD transmission is only really appropriate for 60-70hp maximum out of an RD rev range (torque). That being in road type conditions, it will see accelerated wear, but will be reliable. Even with stock power higher mileage stacks see cracking at the root of the gear teeth. Ive purchased and analyzed a few gear sets and have seen this. Reliable of course being a subjective term.

Look for transmissions based on torque demand and find the lightest unit with good ratios you can. The FZR 600 unit is a good start. You just adopt engine speed to transmission speed via the primary.
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Turning Wrenches / RD transmission questions on hp
« Last post by yellowandfast on Yesterday at 09:10:01 PM »
So, I have has this fairly out-there project in mind for a decent amount of time.
It involves the use a stand-alone motor crank case and a separately bolted on transmission assembly.

The engine will produce 150 hp at the crank. And this particular engine is the center of the project..

Now, what is the hp capabilities of an RD transmission and clutch assembly?
Id like to use the RD stuff simply because I've got lots of them here and I've also got cases to use as well.

This engine/transmission assembly will find its way into an RD 400.
6
Turning Wrenches / Re: Brembo brake upgrade
« Last post by kg23 on Yesterday at 08:51:11 PM »
That looks nice! May I ask what size master cylinder you use?
From own experience with OEM Ducati Brembo brakes, a single 4 piston caliper works great with a 13 mm master, maybe even with a 12 mm.

And what disc did you use? Did you weigh it before fitting it? Did you have to use a spacer behind the disc, for caliper/spoke clearance?
+1 on what master and disc you used.
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Turning Wrenches / Re: Keihin PWK jetting
« Last post by teazer on Yesterday at 08:07:03 PM »
Is there a dyno shop close by that can do a couple of pulls and look at the gas analysis to confirm what is going on?  Mr Barber used to have one at their race shop, but unless you are buds with Chuck or Brian, that may be hard to sneak it in when no one is looking.

http://www.dynojet.com/dynocenters/dynojet-motorcycle-dyno-centers.aspx?Address=Birmingham%2c+AL%2c+USA&usa_distance=25

Any of those close to you?
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Turning Wrenches / Re: Keihin PWK jetting
« Last post by Timnevins on Yesterday at 06:42:19 PM »
Setup a set per the Powerdynamo instructions , and if anything a little retarded ... pickup coil was a little high off the flywheel so I re-adjusted that 👌
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Turning Wrenches / Re: Keihin PWK jetting
« Last post by NCsmokejoke on Yesterday at 06:15:45 PM »
Where is your timing set at? 2.1 is stock, probably should retard that a Little with today's fuel. Not a jetting fix but def could help high end detonation.
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Turning Wrenches / Re: Keihin PWK jetting
« Last post by Timnevins on Yesterday at 05:11:22 PM »
Yep, just pump premium ..
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