Going to be recamming the 550. Input anyone?

I am sending a pair of xj550 seca cams to megacycle to put in my 550 maxim.

valve lift-.350", duration @ .040-244° lobe center will be the same at 107°.

The cams are originally.308/.279 lift, duration 233/228.

It should give me better mid-range and top end but also smoother throttle response.

If anybody knows about this stuff, could you tell me if it is a bad idea or not? This will be done by a pro... not me. Any other internal mods will also be done by a pro... This includes the installation of the modified cams and any piston, valve, and spring mods that may or will have to accompany the change. I am not touching the guts of this one myself.

Just wondering if it could compromise dependability or, if all mods are done correctly, will it not affect reliability. And does anybody know what kind of power gain I can expect?

 

I'm willing to bet that the cams alone won't do a whole lot other than to fatten the powerband where it's already pretty strong.

Remember, cams just control when the valve opens, how far it opens and how long it stays open. Now you have to "improve" on both ends (carb/intake and exhaust) to see any gains from those changes.

Cams are only part of the equation if you're trying to hot-rod a motor.

If you do a whole bunch of other mods, you might gain a few HP but most likely at the expense of day-to-day practicality.

Good luck.

 

I wouldn't do it. Spend the money on a newer or bigger bike.

 

the 550 is a tribute to his friend.

I say go with it...

theres a thread call the worlds fasted 550 or something liek that, where this guy did a whole bunch of work to his 550, until it blew up.

someone on here also found a pair of yoshimira cams on ebay.

Also, seca 550 cams add a bit more power as well... but ya have a shgop do that if it isnt too much money.

You're putting a more free-flowing exhaust on the bike as well, which will help.. maybe go just 1 size, maybe 1/2 size larger jets... I dont know

Cant wait until when you're done with your bike, it will be sweet!

 

Ah right.. sorry, forgot about the tribute part.

My point is: those Yamaha engineers were not stupid. If they could have pulled another 5hp out of that engine with a different cam profile, they would have done it. For a sport bike like the 550, that is. Change the carbs and the exhaust? Well heck yeah sure: now you've changed the rules. But now you're talking a very expensive mod.

I guess my overall point is the stock engine is already at the point of diminishing returns. Meaning: lots of dollars required to get the last few horsepower out of the design.

And as I type all this, I'm thinking about my own FJ-600 out in the garage. That bike has a carb-tuning kit (jets and stuff), a K&N filter, and a righteous Kerker exhaust system and that bike performs WAY out of proportion to its 600cc, 1985 roots.

Who knows? I guess I'm showing my age, when I express surprise that the rich variety of aftermarket parts is... well, is just flat-out unavailable for these bikes. Heck: even the stock parts are mostly unavailable, save for Chacal and eBay. Sigh.

So please: press on with this project. I'll be watching this thread for the results too!

 

Right... was going to buy a Hayabusa and its not the money. This bike is very important to me for a lot of reasons but thanks for the advice. I am still going to get a new one eventually but not now.

 

For sure. I have already done the carbs. Rejetted them with 1.25. First did 1.20 but it wasn't enough when I installed the K+N pods. I have a MAC 4 into 1 with removable baffle sitting in my room right now. I know i am not going to make a monster out of my 550... unless... well... don't wanna. I guess I could have the head redone to fit 4 valves per cylinder and install racing pistons with some wild racing cams and so on... but it's an xj 550 maxim. LOL. Its not a sport bike. Actually just looking for better throttle control and a little more power for when I have my woman on the back.

 

chico Jim is right though, the Engineers did squeeze all they could out of this engine to make it one of the best designs ever, theres isnt much more to do, BUT....


one thing to think about, fj600 jugs on up are a direct bolt on., thats your best bang for your buck, larger valves, cams, etc.

 

I can't wait either. LOL. Got that tank today and sent it to TS Customs here in the area. My buddy Ev and I beat it down pretty bad and it has road rash and dents, scuffs, etc. all over the place. So I named it Road Rash. Its going to be painted on the side of the Black tank in Red letters and am also going to have some pin striping done.

 

sounds like a cool paint scheme

please though, Dont do flat black unless you really want to

now, its almost uncool to have flat black

and flat black is hard to keep clean looking.

 

FJ 600 is a sweet bike. Its where I got my real road ears wet. It had such a different feel than the 550 and way tighter response than the 650 turbo. But that had incredible pull at high RPMs for an 8 valve 650.

 

am going with a high gloss but don't want it sparkley..

 

But, chico-jim... you are right. I always say the same thing to people wanting a drag bike out of their honda 360 or suzuki boulevard. With cars you can do a lot. They make them as economical as possible while giving you a little excitement. With bikes, guys who went to school and have 120 or better IQs spend weeks just figuring out the most efficient way to keep the motor from getting too hot. I am usually the guy saying, the bike was engineered with what it has to be the best it can be. But there are ways to improve it. I am not keeping fuel economy in mind. Haha. But the worst I can do is wreck something and just have to settle with going back to stock.
Another thing is... Another guy I know has a sportster 1200. He is under the impression that a bunch of ccs makes his bike this grea, fast, powerful machine. LOL. The R6 has more bHP than the sportsters stock 70 HP. The xj 550 has 51 HP stock and brand new. But there are a lot of guys who have brought that 70HP 1200 up to over 100 horseys while keeping the displacement the same.
My main reason for wanting just a little more power is, while it performs pretty good for an 8 valve 550 with 2 of us on it, there are times I wish it had just a tad bit more mid range.

 

Cool. We're on the same page.

Heck... if you really want to go for sick fun with your 550, the sky is the limit. Hog out the intake/exhaust ports with a die-grinder (but you're on thin ice here... probably nobody has done it before, and finding replacement heads if you screw-up is tough these days). Know, for sure, there's no room for bigger valves - Yamaha would have done that 25 years ago.

What would *I* do if I wanted to squeeze the most out of a 550?

1. As suggested before, I would bolt on the biggest cylinder block that fits the crankcase. 750? 900? Whatever.

2. Next, I would get the corresponding cylinder head. Duh. And make that head perfect: install fresh valves, guides, and 3-angle valve job.

3. Find a way around the primitive electronic ignition. Adapt or install an ignition where you can easily set the initial advance, and then program or taper the advance curve on up the rev range, up to redline. While you're there, install or program a rev-limiter that corresponds to redline.

4. Adapt a fuel injection system from some other bike. Ditch the carbs! Serious: there must be other 600cc-range bikes that have fully-programmable fuel injection. Find one at a scrap yard and BUY IT! This will save you hundreds of hours dicking around with the fuel system, and (relatively) primitive carbs from the era.

5. Improve the exhaust. Find a great system from past-great companies: SuperTrapp, Kerker, V&H, - they all were competing for the best systems, price and performance at the time. Make your own system? Noway. Don't re-invent the wheel - the companies that I've listed here have BEEN THERE. Find such a system at a junk yard or on eBay.

Again, I've rambled on too long, sorry. But hey: if the sky is the limit... to me, these 5 things would put you there. Careful adjustment and programming of all these items would enable you to create the fastest 550 EVER.

 

It depends on your point of view, the engineers were building a bike to last a certain amount of years and a certain amount of km while being ridden and maintained by hamfisted monkeys so they were only aiming so high as far as performance went

 

And then WE come along, some 25+ years later, and screw up their whole philosophy. (Except maybe the hamfisted monkey part.)

I often wonder if the crew in the little musty shop on Bracebridge Street ever had any idea that the Norton they assembled back on a cold morning in February 1974 would still be running and on the road 35 years later. But then again, maybe they did...

I'm reasonably SURE that the legion of Yamaha engineers that designed and built our bikes had NO intent that we would still be riding and trying to maintain them a quarter of a century later. Honda seems to understand, and actually makes a point of supplying parts for their old bikes; you would think Yamaha would catch on as the parts continue to sell.

With motors as cheap as they are, if your mill is in decent shape, I would pick up another motor to "build." Once done, swap 'em. If it turns out it was a mistake, you'll still have the original motor (with matching serial number) to put back in.

 

Don't go too far with any one mod, the engine should remain "balanced".
Nobody mentioned raising the compression? that's "free" horsepower.
You have to clearance the pistons anyway.

http://www.xjbikes.com/Forums/viewtopic ... stest.html

Read some of his posts ^ ^ very interesting stuff

 

Well if one of your big concerns is making those Broken Down Water Pump Riders (Harleys) look bad then restore it to stock. I would say that less than 10 % of harley riders have modded there bikes beyond visual stuff. My XJ 550 made my friends Sporster 1200 look slow and his has aftermarket exhaust and baffles and increased performance. My other friends street bob 1400 couldnt even touch the 550.

 

Haha. Ya... I had a guy pull up next to me on a Dyna one day. His was Yellow with flames on the tank and fenders and had loud screamers. He was revving like he wanted a quick drag and when the light turned green we took off. Well, I took off. He tried but Yamaha was and still is all about performance. These bikes are just quick as hell up to 75 or 80 mph. Nothing like a yzf or anything but I can keep up with a stock R1 til about 60. But I am in 2nd gear by then and his R1 still has head room in first.

 

I was actually thinking about the fuel injection option. Seriously. Its the throttle response and, well, starting the bike without hassle. I was actually wondering, after I saw one for sale on ebay, if the FZ or R6 injector could be used for a 550. It didn't look like there would be too much conversion involved as far as installing it and I would think, with some mods, I could get them set to the right fuel/air ratio. But don't know enough about those to really know what I am talking about.
And when it comes to electrical and electronic components and hardware, I am lost. You seem to really know what you are talking about, chico and don't worry about rambling. But I would definitely need to have a lot of explination about some of this stuff.
As far as finding the block and head... I'd just get the whole motor and rebuild it, if necessary. But something about keeping the same displacement is really keeping me from that change. I dunno... I mean, I am going to get a new bike when I am done with this one. Not interested in the Busa anymore. Youtube ruined that for me. But I like the FZ and YZF-R bikes... Love the FJR except for that electric shift craziness. Besides, I wouldn't get a bike like that yet. I am still too squirrelly and hyper.
I have wondered about the possibility of just boring it out to make a true 550 (or like 554) instead of 528. But that would take more goofing around than the cam job. For now I am going to keep it the way it is (aside from the injection idea) until the engine needs a rebuild. So far my compression tests were right on stock before the carb job. The valves need to be adjusted and maybe cleaned and polished. And I want that damn cam chain rattle to go away.
I was thinking, also, until the time comes for a rebuild, going one smaller on the front sprocket and 1 0r 2 larger on the back. It would, I am guessing, make 2 up easier on the motor. It would reduce my top speed but increase my quickness I'd guess.
OK... now that is rambling. Haha

 

A set of stock 600 pistons which are 58.5mm compared to the stock 550 at 57mm will take it out to 557cc and you can do it with the just reboring the stock liners

 

Dammit... The 600 pistons would have been perfect. I had an FJ 600 and sold it to eric who sold it to dave uphoff who dropped it off the back of his truck... etc.