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Discussion Starter · #1 ·
People have been putting turbos on engines for a while. I know the 500T is fuel injected, but doesnt have to be to make the turbo work. If I found the manifold and turbo, could I give my bike a little boost? No pun intended.
 

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Yes, but with the caveat that unless you were to be running very low boost the engines compression would have to be dropped significantly.



As there are [to my knowledge] no suitable pistons available for the CX you would be looking at considerable head work to lower the compression. Not impossible but.....



Possibly non vac [CV] carbs would also be needed. These carbs are sensitive enough to changes in vacuum without forcing the charge through them under boost.
 

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How about milling the top off the crown of the piston? If you look at high compression pistons vs the standard issue items, the upper crown centre is much higher thus increasing comp. Surely lowering it would have the opposite and desired effect? Maybe installation of the 500 turbo cam would be adviseable too. I understand turbocharged engines run greater overlap with the valve timing.



Could be a great project this.
 

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run a bigger single carb... like off a 1000cc v-twin.... harley perhaps? or shadow? or vulcan? and with boost jet them carbs rich as hell (you can always go leaner later) or you will be looking for a new pair of shorts and a new engine after sweeping up your cylinderheads across 3 counties if you get detonation at 10grand
 

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Discussion Starter · #9 ·
There are lots of things I would need to look at before spending any money on this. I'm sure my bike would would hit 10k RPM's but I don't think I will ever try it. Modded or not. Well, actually I think the Ignitech has a rev limiter set, not that it isn't made to be changed. But I won't.



This isn't something I'm going to jump into blindly. Not even any time really soon, unless the parts become available at the right price. I suppose a bottle of NOS would suffice for now, for those times on the highway when I need a little extra power.
 

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How about milling the top off the crown of the piston? If you look at high compression pistons vs the standard issue items, the upper crown centre is much higher thus increasing comp. Surely lowering it would have the opposite and desired effect? Maybe installation of the 500 turbo cam would be adviseable too. I understand turbocharged engines run greater overlap with the valve timing.



Could be a great project this.
This COULD work, but I don't know how advisable it would be to remove material from the head of a piston, weekening it and then ask it to take more stress under boost.



If the piston is already grossly overengineered it should be OK but I'd be very uneasy about it if it were my motor.
 

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People have been putting turbos on engines for a while. I know the 500T is fuel injected, but doesnt have to be to make the turbo work. If I found the manifold and turbo, could I give my bike a little boost? No pun intended.
I built my first turbo bike in 1978 and used my retired CB750 roadracer. I bought a Rajay turbo from a KZ900 and manifolds from American Turbo Pak. I couldn't afford a "turbo" carb so I used the one off my Honda 250 Elsinore. Hooked up oil and drain lines and ran it. The bike had a heavy duty clutch, ported head, Norris cam and springs and ran great. I didn't run much boost but it was a lot of fun. The turbo probably added about 15 or 20 h.p. and about 10+ mph. Later I added a Kawasaki 750 turbo and then a couple more. After that got into the CX500t's and 650's. They are all neat bikes. I am considering building a scratch CX for landspeed racing. Honda has done the bulk of the work for us. They have build the bottom end that works, an ignition that retards the timing with boost, fuel injection sorta designed for turbocharging, pistons, heads, manifolds etc. For a street bike I would probably try to get as many factory parts just to avoid having to fabricate anything. Maybe use the Yamaha turbo carbs if you don't have to build your own blow-through carbs. Use the factory exhaust cause it is efficient. Stock pistons would probably handle 6 - 8 #'s of boost. Get your jetting perfect and watch for detonation. If you want to go more complex you will need pistons, call JE pistons they can make them. I would get about 8:1 and ask for thicker top ring lands. For fuel injection I would look at a microsquirt system. Keep us posted if you go on.
 

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CXPHREAK: Fair point with regards to removing material then asking the piston sustain more load. Maybe use of 500T pistons (if they're at all available) would be an option as opposed to modding existing parts or paying out big £$$£ for cutom items that may or may not get grenaded!
 

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I think the biggest caveat for fuel injection (naturually aspirated or force induced) is the necessary addition of a high pressure fuel pump
If the bike runs either a blow through carb or fuel injection it will need both a fuel pump and a regulator. Those are both simple and cheap to install. A carburetor just needs a little more pressure than the boost you are running, fuel injection will need more, probably somewhere in the 35 psi range. I added a link a few months ago about adding f/i, do a search under my replies to find it if you are interested.
 

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This COULD work, but I don't know how advisable it would be to remove material from the head of a piston, weekening it and then ask it to take more stress under boost.



If the piston is already grossly overengineered it should be OK but I'd be very uneasy about it if it were my motor.
You do not want to modify the stock piston. It is already at optimum size and thickness. Taking an 1/8" or more off the top would invite disaster. Either find some used 500t pistons or have JE pistons make some. They have the specs for 500's and 650's and it is just a matter of telling them the compression you want. If I was building a street engine I would run more compression as I said above, somewhere between 8 and 9:1 and then run less boost than Honda did. The extra compression will give you more torque down low and shouldn't require too much more ignition work. If you plan to run 18+ psi of boost you will have to have an ignition retard system.
 
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