I hope this doesnt provoke hostility

[wickedRadian]

Hello everyone, since im new here on fjowners.com i would like to get out in the open my super project bike that you all may or may not love.. i built this bike last winter for the second time. it started out as a basket case radian that i totally fell in love with. however the lack of power and a severe oil consumption problem forced me to make a decision that would end up costing me a significant amount of money (for a 21 year old that is) either way. either build a hairy 600 that would be tempermental and probably only 90 hp (and hard to buy parts for ) or to swap engines.. as im here you can imagine what i chose for a donor.. all went well i will post pics when i figure outhow...
http://www.fjowners.com/index.php?action=gallery;sa=view;id=6650

[Steve_in_Florida]

Nice project!

You certainly don't lack ambition.

Randy at RPM is one of our resident engine & parts guru: http://www.rpmracingca.com/

I'm sure he can answer all of your questions.

Welcome to the forum.

Steve

[wickedRadian]

im going to have to call him or something because i do not see any hotter profiled cams on his site thank you steve!

[Arnie]

Hi Wicked,

Be careful with Megacycle. Read about how Randy on behalf of Bozo has had difficulty in getting any help from them on a defective unit.  There have been a couple of additional stories of hopeless customer non-service too.
Most of the big power FJ engines here have been stretched to larger sizes as well as normal hot up procedures.
There was a guy in Ontario CA who had a streetable FJ showbike called Black Sunshine that fitted both a supercharger AND NOx to his FJ.  Note: he eventually sold it and went to Hyabusa for more modern design and power.
Have you actually shoe-horned an FJ engine into your 600 Radian ?  And you think a stock FJ isn't strong enough? Really??

My opinion is that you'd be better off with a 'Busa or Kaw ZX14 engine that you can hot up more.  You'd at least be starting with a current design which is already putting out ~40 more hp than the FJ.

Arnie

[movenon]

+ 1 on what Arnie said. Your bike looks great ! Post some more pictures. You are in the right place here. In my opinion the FJ has all the power you can handle in that bike design. Which by the way I like. Keep posting.  You can pick up a whole FJ engine for 500.00. TQ and HP....
George

[rktmanfj]

Have you actually shoe-horned an FJ engine into your 600 Radian ? 

It would appear so:

[wickedRadian]

thanks for the input everyone! yes i did fit the biggest engine i could find in my radian.. it was one of those nights when a few too many beers hit my medula oblingata lol.. i have always dreamed about this bike (in a round about way) ya know the one that looked flashy, was comfy, handled well, but mostly wasnt a "crotch rocket"... and therefore  :empathy:didnt make a zing zing noise when you punch it (i hate that!).. yes the chassis is not meant for 165 mph, but thats has not been aproblem.. it doesnt need to go faster, just get there quicker

[wickedRadian]

and please dont tell me, anyone, that i need to re gear it because ive been there.. there always seems to be a dead spot

[Country Joe]

As a former Radian owner and a current FJ 1200 owner......

    Joe

[Arnie]

Dead spot, huh?  Well, the "dead spot" in the FJ's torque curve is mostly dealt with by the OEM air box.  I bet you've removed that.
Can you replace the air box?  Do you have access to a dyno and the sonics credentials to build your own?
You could change the gearing so you pass through that 'dead spot' quicker, but you don't want to.
You could lighten the crank and bob weights and clutch as much as possible to spin up quicker, or you could start your run above the rpm where the 'dead spot' is.
Most hot cams give you a few more ponies up at the top of your rev range at the cost of rough running at low to mid range revs.
You've gone this far, why not hog the engine out as far as you can to a 1350 or so....that'll get you some more torque.
I don't think you're gonna find that magic pill to answer all your desires.

[oldktmdude]

Dead spot, huh?  Well, the "dead spot" in the FJ's torque curve is mostly dealt with by the OEM air box.  I bet you've removed that.
Can you replace the air box?  Do you have access to a dyno and the sonics credentials to build your own?
You could change the gearing so you pass through that 'dead spot' quicker, but you don't want to.
You could lighten the crank and bob weights and clutch as much as possible to spin up quicker, or you could start your run above the rpm where the 'dead spot' is.
Most hot cams give you a few more ponies up at the top of your rev range at the cost of rough running at low to mid range revs.
You've gone this far, why not hog the engine out as far as you can to a 1350 or so....that'll get you some more torque.
I don't think you're gonna find that magic pill to answer all your desires.

Arnie, I haven't got the air box fitted to my FJ and I haven't been able to find any "dead spots" between 1,000 and 12,000 rpms. More than likely a jetting issue or needle position problem. Doing the 4* ignition advance might also help.  Regards,Pete.

[wickedRadian]

thanks for the input guys, but my dead spot is 8500rpm and up so we shall see..  the thing needs to be freshened anyways.. have any of you seen any dyno results from partially modded 1200s? im searching for 150 to 160 what is the best combo you all have found?

[fj1289]

Dead spot 8500 RPMs and up?

Sounds like a fueling issue. Might be main jets -- but thinking the fuel system isn't keeping up with the engine demands at high rpm use.  Does the Radian petcock flow enough to feed the 1200 engine?  I'm guessing a high flow petcock is in order

Great project!  Any details on the swap?

Chris

[wickedRadian]

Dead spot 8500 RPMs and up?

Sounds like a fueling issue. Might be main jets -- but thinking the fuel system isn't keeping up with the engine demands at high rpm use.  Does the Radian petcock flow enough to feed the 1200 engine?  I'm guessing a high flow petcock is in order

Great project!  Any details on the swap?

Chris

it was a lot of work, easiest part was wiring.. hardest part... umm chain to frame clearance and alaignment was huge..  i would have to say the overall experience was eyeopening but next time im building the whole thing from scratch

nothing like trying to fit 10 gallons of shit in a 5 gallon sack right?

other than that im not shy ask any details you want

[andyb]

If you're getting a dead spot from gearing, you're doing something comically wrong.