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FZR carb conversion

Started by Walt_M., May 18, 2016, 06:09:43 AM

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Walt_M.

Well, I almost blew it up yesterday. I put the 32.5 pilots and 52.5 starter jets back in. I don't have a very good throttle cable setup so I have to do a crude cable position adjustment when I put the carbs back on which involves WOT with the throttle lock on. I am kind of amazed that it started with the throttle wide open! Got it shut off with no immediate damage. Restarted it when my heart rate returned to normal but I decided to wait for the test ride.
Whale oil beef hooked!

Rikugun

I'm guessing that was an exciting and horrifying few seconds that seemed longer as it was happening.  :)
It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

Walt_M.

Finally got my test ride in this morning and I am happy to say that I now have a runner. It starts well, accelerates well. Steady state cruise is good with no surging or stumble. The brakes are good enough with the EBC pads and I am happy with the handling with the new Conti radials is very nimble and not at all twitchy. I still have plenty to do, it is still a Vision, but I can ride it as it is.
Whale oil beef hooked!

fret not

Walt, that must be a huge relief to have accomplished your goal.  That's a big mountain to climb, and you did it!  You have put some fuel on the fire for the rest of us to get busy and just make it happen. 

Right now I have some parts and pieces, and I'm definitely heading up the mountain, but by a slightly different path since I have different carbs and elected to make the manifolds fit the carbs. 
Retired, on the downhill slide. . . . . . . . still feels like going uphill!

Rikugun

Nice work Walt, I'm glad it's worked out. Nothing left to do now but put miles on it!  :)  Oh, and fix any of the other Vision peccadillos.

It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

Walt_M.

Well, there is always the R/R. I think I will try the series type as I don't believe going to a MOSFET would do anything for the stator.
Whale oil beef hooked!

Walt_M.

#106
A mind is a terrible thing. I got bored yesterday and disconnected my fuel pump. Put it on prime for a minute or two and it started right up. I guess I don't really need it unless for really low fuel level. It has less than 2 gallons in it now but it is not on reserve.
Decisions, decisions. I have determined that the pump will not pass fuel if it fails but it may not be able to use the last bit of fuel without it.
I think I will keep the pump since I already have it. All I really need to do is get it mounted better. If it fails out on the road, it would take very little to disconnect it and be on my way.
Later this morning I was doing some pilot screw adjustments and was not having much success. It finally started slowing down and as I was adjusting the idle speed up, it stopped. Carburetors are empty. Put it on reserve and reconnected the pump, put it on prime and it started right up. Futzed with it some more. Side note, it is very to reach the throttle balance adjuster screw with my setup. Anyway, I got it where I wanted it and took it for a test ride. I wanted to try something with the air box. I was going to punch some holes in it but as I would have to fix it if it didn't work, I just left the top off and tie wrapped the filter in place. The ride was short and loud. I can say it ran okay but probably not better. At this point, I am going to run the air box top undrilled and go another step or two leaner on the mains.
Whale oil beef hooked!

fret not

The air box and filter help keep the intake noise down a bit, so I would vote for keeping them in place, at least until you can come up with a more efficient set up.
Retired, on the downhill slide. . . . . . . . still feels like going uphill!

Walt_M.

It was truly annoying so the top goes back on. It is a non-modified '82 top with the flapper completely removed. I like the design of the thing and am not convinced that it needs a bigger opening. I am going to go leaner on the mains but I'm not sure how much, just wish they weren't so expensive and I didn't have to order them.
Whale oil beef hooked!

Walt_M.

Finally made some progress, front brakes this time. I got a set of the blue/gold spot caliper adapters and a set of gold spot calipers. Had some scary moments with fit but I got them on and I have to say it was worth it. I used the stock Vision master cylinder and it gives good feel with one-finger power. This thing is getting to be a pretty good motorcycle! I did put the stock air box top on, just cut the standard opening a little bit and it ran good and I am happy with the return of the quiet intake.
Whale oil beef hooked!

fret not

So it sounds like things are really coming together nicely.  Congratulations to you for your accomplishments!   :)
Retired, on the downhill slide. . . . . . . . still feels like going uphill!

Rikugun

It's amazing how the simple things can really make the difference in enjoyment. And when I say "simple things", in the case of motorcycles I mean brakes that work and carbs that fuel properly.  :D
It is far better to grasp the universe as it really is then to persist in delusion, however satisfying or reassuring.  Carl Sagan

Walt_M.

Also can't leave out the radial tires. As I had previously stated, I had never run a 90/90 front. It is an '83 and came with a 100/90 and due to what I considered excessive wear, I went to a 110/90. Can't say much about the wear but it handled like a truck. Now it is a joy to ride. It is both agile and stable, I really would like to have a set on my RZ.
Whale oil beef hooked!

QBS

#113
Walt, thank you for your commitment to your journey and bringing us along on the adventure.  You have seen it through to the end (if such journeys ever have an end).  I am happy for you and look forward to whatever new developments may unfold.  Thank you!  Well done.

Ron_McCoy

Wow! How did I miss this thread? I recently finished my own FZR carb transplant on my 82. Starts easily, idles nicely, no stumble or hesitation, accelerates really hard and pulls to redline (and beyond). Haven't checked the fuel mileage yet due to refining the jetting and generally riding it pretty much wide open during testing. Amazing how much nicer it is to ride.

fret not

Ron, how close to the way Walt did his is your installation?  A write up of your process will be welcomed, and may help others to do much the same.  Pics too please. :)
Retired, on the downhill slide. . . . . . . . still feels like going uphill!

QBS

Ron, I'm particularly interested in knowing about your manifold solution.  Pictures please.

Ron_McCoy

#117
I machined aluminum adapters to plug into the vision rubber manifolds with the upper diameter the same as the FZR carburetor throat o.d. And connected them with 1 1/2 " Gates fuel proof hose, the type of hose that connects the filler tube to the gas tank on a car. Also velocity stacks to adapt to the rubber velocity stacks in the stock air box. Meantime I moved to another town and this project got dropped for a while. The vision sat for a while due to a starting problem and misfire at low speed which ended up being a defective pickup. Once I got it going again, I fabbed cable stops for the throttle and choke and worked out the plumbing on a spare engine I have on an engine stand, which made things a lot easier. Much of the installation resembles Walt's from what I can see from his pictures, tubular spacers and so forth. Mounted my cable stops on the spacers and sectioned and welded the FZR choke linkage. I used the vision throttle and choke cables. Next time I have it apart, I'll take some pictures and post them. Right now I want to do some riding before I tear it apart again.

Congratulations Walt. Quite an accomplishment on this bike. This is how Yamaha should have done it in the first place.
Also did the series rr installation. 14.2 volts at idle, 14.6 at 3000 rpm. Rr is up in the fairing. Rr Temp dropped from 130 degrees to 105. Stator case at 180 degrees after 40+ miles of canyon riding on 98 degree day.

Walt_M.

Ron, it sounds like you preceded me with this swap. I am sure your machined adapters are nicer than the things I made but it is the same principle. I am very interested in your jetting. I had some sir leaks at first that led me to think I needed to go richer and I did. As I have stated it is rideable now but it could be better. Did you keep the fuel pump? I do appreciate the info on the series R/R, encourages me that it is worth doing too.   
Whale oil beef hooked!

Ron_McCoy

Walt, I have #35 pilot jets, #135 main jets and the starter jets that came with the carburetors. I'm running the stock fuel pump. I started off without it, but got to thinking about low fuel levels and it was easy to mount the pump. I haven't done an engine kill plug check yet due to how much fun it is to pull a plug on the side of the road, but it pulls cleanly past redline in the lower 4 gears(haven't done a top speed check yet) with euro gearing and runs just below center on the temperature gauge.
I think the series rr is a good thing. I was running over 15.5 volts at speed with the vision rr. The engine in my bike now has just over 17,000 miles on it and is still on its original stator which looked pretty good when I changed out ignition pickups. I live in the mountains about 4 miles from a small town( 6 stop lights ) so most of my riding involves a lot of miles and little traffic.