XJ and quite frankly, cycle noob.....

Getting started..... XJ550RH. Some of you have already purchased parts from me, and all of you have welcomed me. I'm going to be tearing into this thing soon. Here's what I'll be checking:
Valve clearance, clutch condition, I'll be bagging and tagging the Mikuni BS28's.....

Here's what I know I'm replacing and/or refurbishing:
-Front brakes; pads, caliper and master rebuild, braided hose.
-Jets, 6 sigma. I read the thread. No pods, thank you. But I aquired this bike sans airbox. I have an idea for my own box using a k&n panel filter, baffles and velocity stacks inside...And Len has me covered once i dig into the carbs....
-Petcock, and tank, but where do I find the old formula kreem? This new stuff doesnt seem to work. Or do I run it dry
-While we're on fuel....I havent been able to find out for sure if this bike has hardened valve seats... The shop manual talks about cutters for reseating, as if they mean hand cutters, which indicates to me the seats arent hardened. Lead additive?
-Oil filter??? I know this may seem stupid, but the crap i deal with using Napa filters (i.e. ford 6.4 diesel fuel filters wont prime) has taught me to never skimp here. Whats good?
(I read about the Jaso MA oil but I've had a few wet clutch dirtbikes, so i won't screw that up....again)
-Fork fluid. This things been sitting so I'm throwing all liquids in the waste oil burner at the shop.


So here a just a few of my questions....
Can I buy just the valve pads I need? Or do I spring $130 for a kit?
Clutch discs?
Is there a block off available for the tach drive? (if not, does someone have a threaded cuff from a wasted cable I could buy to tig shut and install to cover the unit?)

All ideas, cautions and advice will be appreciated! In the meantime, i'll keep reading.

Thanks-Nate

 

Oh yeah, And rear brake shoes....Thanks Fitz

 

do yourself a favor and put out a APB for a airbox. unless it's just something you want to do, then go for it.

dry if it don't leak, but Caswell has stuff that works, try not to use Kreem.

no, regular pump gas, no lead additive necessary.

stock ones work just fine, see chacal about a spin-on adaptor

Hogfiddles has a shim pool

see chacal

i don't think so but there should be.

 

I saw (I think Len) had the tach block-off. I re-built mine, but I know you're going a different direction, so check with him.

 

Thanks Polock, Dave. I love fabricating, this airbox thing looks like a challenge and thats attractive. However, the right way to do it is to have a baseline. I would need dyno results of a stock unit to compare to. And I would be looking at strictly power gains, losses.... I'm mostly interested in flat spots. Because if the torque and hp curves are smooth, and slightly resemble that of a stock bike, they can be raised and lowered with fuel and timing. Plus if I dyno the bike I'll be able to see afr's. I saw the ingenious little plugs in each header primary....

 

(WOULD NOT be strictly looking at power...)

 

+1.

Gary H.

 

Chacal does carry the tach-drive block-off, and has thm in stock.

The math to determine airbox volume isn't too difficult, and since you're not after making it anymore of a hot-rod than it already is you won't need to get into the math required for figuring the airflow characteristics to improve cylinder filling. For a baseline you can build a mock-up facory airbox out of card and play with that volume for packaging purposes if you can't find a factory airbox.

 

I mean, my idea uses basically the same cavity in the frame. It's not a "ram air". Just a box with baffles and long velocity stacks inboard. I'll use a panel filter where the air comes in and it will be sealed. E46 BMW M3 has this same concept in use on their plenum design, also, this way I can position the crank vent to utilize the stock hose. I believe volume is as easy as HxWxL=V I'll most like use metric to calculate cc's. From what I've read, the stock airbox makes the carbs tricky to get off. That may explain the few fragments of black plastic that were in the bottom of the Tupperware tote I received the carbs in.... I fear that is what remains of the stock box. My idea will be assembled in sections so as to facilitate an easy removal. I invision polycarbonate sides to this airbox, allowing one to view the velocity stacks and chambers from the sides. I plan to run an antigravity 8 cell, laying flat, tucked under the seat pan, behind the airbox.... Off to work now to sort through the box of aluminum 2" mandrels. They will fit tight over the outside of the coupler boots, just as factory, bend down to clear the frame. All of equal length... Soon I'll draw my idea to share. A little paint by number lol.

 

Anyone else on the hardened (or not) valve seats? I'm quite paranoid about running pump gas without lead additive, sans knowing they are hardened. Can you hear me chomping my nails? Also, whats the best miracle juice for preventing those pesky enzyme deposits thanks to the ethanol....... And I wonder.... Have any of the policy makers that required the ethanol done an analysis on the carbon footprint of all the carbs and related parts the average consumer is throwing out prematurely? Perhaps a topic for another thread... I've been using startron with my lawn equipment, but that's lawn equipment. None of my Briggs and Strattons redline at 10k....

 

Do not worry about a lead additive. I know of no one on this site that uses it. I used to use it in a 75 IH Scout II but that is a topic for a different forum . . . . .

Ethanol, is an unfortunate reality. My experience/ understanding is that as long as you aren't letting it sit for extended periods of time it should not be a problem. Ride the bike often, take good long rides (tell you significant other that you HAVE to go for a 3 hour jaunt because it is a maintenance procedure . . .) then when winter comes, add some Stabil to the tank, or top off the tank with non-ethanol premium and call it good. Some folk drain their carbs in the winter.

 

The bikes were built to run on unleaded. Says so in the owner's manual.

Some folks don't worry about using ethanol blended fuel either (E-10), because that was around when the bikes were designed, and Yamaha took that into account (use Stabil's ethanol product for winter storage though).

 

Off topic.... Hey Len, I got my money on the Falcons! It's time for a shutout against new England!

 

Nast.... let me know what sizes you need

Dave

 

lol. You Mean Champion T's? That Say Patriots?

 

Seriously though....If your referring to valve shims, Awesome! I suppose your pool is a trade? Plus Donations?

 

so close yet so far

 

That was an exciting game though. So back on topic. I'm thinking airbox removal is suicide because the fine engineers at Yamaha had carefully constructed a resonant box. My guess is that with these puppies revving to 10k, theres a bit of valve overlap. They probably made the midrange crisp by taking advantage of resonant frequency. Do these airboxes have an inlet tube? Perhaps with a bell mouth? I only have external pictures so far to referrence. Btw.... velocity stacks on the way. So...... would I be the 500th moron to attempt this?

 

Also , looking at the diagrams, I am thoroughly impressed with how the bs28's operate. And I can clearly see the air jet being as important as fuel. Theres a symbiotic relationship between them all. Careful timing of diaphragm actuation, fuel atomization. I'm quite excited to even get this a little wrong. Well above my paygrade. But I've found some incredibly interesting articles written by engineers giving up some formulas. I need math tutoring..... K-Moe? You were saying something about volume?

 

Oh and thanks for the manuals Paul!

 

http://www.saltmine.org.uk/randy/airboxdesign.html

I'm sure some of you have read this. This was one of three i've read so far. This one was a quicker easier read. I'm struggling with the ones that use equations. to me "x" is to multiply. I believe to the mathematicians, "*" is multiply....and so on and so forth. So much for my GED. Now, I need to back track and read articles for math lol.

 

Quote from another forum: "Yes, the usual equation is D=(CIDxVExRPM)/(IVx1130). Assuming very good preparation for your engine, that works out to:

D=(97x0.9x9000)/203,400=3.86" diameter (~98mm)

If the head work is not first class, use 0.85 for the VE instead of 0.9. The 180 in the second term is intake velocity in feet per second. 180 is a good number, but if you prefer another, go ahead and use it."


Which is of little value to me, because I dont know how to calculate the volumetric efficiency of the 550. Anyone have an airbox available from that pool?

 

the air box has a slot across the top rear of it maybe a half an inch wide going the width of air box .

many people have tried no air box plenty of threads on it only one person has claimed success and his "friend did it for him" so he does not know what was done.

the last person who was going pod had a thread stupid carb questions and was going to try changing up the slide needles . have not heard back from then in a while

 

the air box is an odd thing . In my opinion Yamaha designed an air box to fit the frame and not a frame to fit an air box. 550 maxim different part than 550 seca.
if you look at an air box it has 2 compartments front compartment centered on carbs and rear compartment off center(because of battery) to hold the air filter and a hole to fit the foot print of the filter.
the stock air filter is what the box is using to establish air flow as well as the slot for air. the critical part of the box is the forward compartment .
that part is what needs to have the volume, cubic inches to share with the carbs and handle how they interact with each other.
we had a member who made a front box and attached a filter to the rear.
if you take the front chamber and duplicate the cubic inches you should be able to get in the ball park.and be able to tweek it based on pressure drop of the filters you use.

I used to work at a place where we made air filters and we would measure the pressure drop of the filters , test equipment was just a box with a vacuum gauge on it place the filter over the intake and measure the drop.

edit
the air box boots are a critical part and needed.
the air box was built for performance AND fuel economy . it balances the vacuum used to open the diaphrams and collects the fuel backwash from the carbs it also takes advantage of kick back from the carbs to give a slight turbo or supercharged effect.

so if you design your own system to be able to put pods on you lose the "coolness" of the pods
and in the end trying to reinvent the Wheel.

alot easier to find an air box use it and spend your time riding.

 

edit: this is a maxim air box you can tell by the metal clips and post with grommet on it for mounting side covers.
it is said they max will not fit the seca do not know if it is a frame thing or just the mounting tabs





I do not know if there is a part number on the box

 

I am the proud owner of that thread

I actually made some modifications that I tested before the bike got put away for the winter. changes were to exhaust back pressure and to the jet sizes and the small ride i took was a huge improvement. Once i can test again and actually take it out on the road i'll report back.

My 2 cents. If you want an airbox buy an airbox, recreating one will be a pita and might leave you with the same issues as pods. If you want pods go with pods. If you want a chimera, i say go for it. Easiest thing is the air box. Just remember chicks dig scar and pods.

From all my research I can say pods do create an airflow problem, its not so much the volume but the speed. Sucking air through a straw vs sucking air through a paper towel roll. While the paper towel is more, its slower and doesn't produce the pressure to raise the diaphragm as certain RPM's. There are different approached to tackle this:
1: Modify the pods to smooth out airflow and speed it up
2: Modify the needle and air jets
3: Play with all jet sizes to get the right combo.
4: Buy a slide carb body and call it a day

 

So based on that picture, I'm not far off... Yes from what I'm reading, that kick back, is the resonance. Similar to what the exhaust collector box is doing, but not identical. The exhaust side is taking advantage of the scavenging effect of pairing cylinders that fire every other.... to avoid pushing backpressure up the wrong tube. Or so i've read.... Thanks for putting that up Paul! Also, I ditched the pods idea a while ago. THanks all!

 

Also, thats why I'll use velocity stacks. The stable air in the box will increase speed right at the carb spigot. This will channel in to the diaphragm lifting it.

 

Corrct on all points and questions.

 

Exactly!! That's why the factory airbox boots are velocity stacks (look at the internal diameter when you get the chance).

 

I'll add:
5: play with slide springs
6: play with air jets
7: play with drilling the slide

 

Thales airbox boots I have, are not of the velocity stack design. Hang on. I'll post a picture. Again I don't have the airbox to look at...

 

They are also covered in some kind of sticky goo. Like the slop that came with my uni pod for the moped.

 

I see somewhat of a transition.... but no velocity stack.

 

That transition is all the velocity stack that the carbs call for with the factory airbox. You'll notice the difference if you ever try using radiator hose for airbox boots, or the unshaped boots that most pods come with.
Not saying that you can't go with a different profile, just that Yamaha did engineer the system to work with the existing valve overlap. Yes there were packaging compromises made, so if you're ambitious you can likely engineer a better airbox and intake system with the extra room a smaller battery will give you.

 

Where I lack ambition, I am abundant with stubbornness! Lol

 

Cranked it over using the starter tonight.... Starter sounds like clock works.... And the engine said GLUG!GLUG!GLUG!GLUG! with the plugs out..... Used the old finger over the whole method and nearly lost it.....VERY EXCITED!!!!!! That valve cover will come off soon Hogfiddles. I gotta work through this airbox thing, once thats engineered, I'll be pulling the carbs apart and measuring the valve clearance. Looks like the velocity stacks arrive for Valentines day, I'm digging into cad for the mounting plates..... Patience... Yet I'm sure once I'm riding it, I too will be missing it needing work! (I'm sure I'll be playing with carbs till the summer of '18) At least I have that going for me LOL!

 

A little mock to test my measurements for spacing. The flange will actually sit on the velo stacks, as the stacks are a perfect fit for the spigots. The challenge will be with the welding. The flange will be made into 2 halves, as the diameter of the velo stacks at the weld point will be smaller than than either end. I triple checked my measurements before working in cad. Fingers crossed. The fine folks at Decker wont be loading this into their water jet for free!

 

Something like this.....

 

once I get the velo stacks and get more precise (0.00mm, instead of 0.0mm) measurements plugged in, make room for the idle adjustment mechanism, and make the other parts (planes) for the box, I'll include volume calculations, panel filter part number, hardware list, and tuned pipe length/diameter variations to theoretically place airbox resonance in coordinance with specific rpm ranges (+or- 500rpm). I'll have to start a new thread over in XJ mods on this. I'll post pics and share cad files with anyone interested.

 

rough idea of where I'm headed.......

 

I've gotten pretty decent with solidworks if you'd like me to work something up for you. I could make stacks with a smooth curve, if that matters.

 

I have actual stacks coming. They are smooth. And it does matter! Thanks Dave! I'm crackpot on the fly learning FreeCad. I certainly have not yet figured out how to model the stack transition smoothly yet....Is there a common file type among the cad programs? Also I do not know the exact diameter of the bell mouths of the stacks.

 

This is heading towards the appearance I had in my mind, although the spigot bulkhead, and rear bulkhead would be aluminum, and the polycarbonate would be a band, heated in the oven, formed around a wooden mold, then slid on to the bulkheads and fastened, most likely with counter sunk jis phillips panhead....or something authentic. Something mildly Gaudi...... just for me lol.

 

Also, it took me quite a while to get this far. And merely for the sake of the experience. I doubt I could afford your CAD experience Dave! I have to say though, this is definitely getting my brain juice churning! I dream of a shop with all the goodies! CNC everything! And an A/C inverter tig.... (drool drool).

 

Bonus points for the Gaudi reference! Not your average motorcycle forum.

 

Lol. In spite of the social decision to use that man's last name as a kind of derogatory slander, I appreciate his art. And although I see how the richness and complexity of his designs can be taken as a form of bolstering, or perhaps elitism, to me, it is warm with color.... And I think he inspired a lot that society accepts....

Ehh? Am I right?

 

something to think about with your airbox design.
the v stacks you have placed inside the box are robing you of cubic inches that are contained in the air box. you may have to increase the shell size.

 

Good news for architecture fans:
Word History: There is an urban myth that the eponym of the word gaudy is the 19th century art nouveau Spanish (Catalan) architect Antoni Gaudí i Cornet (1852-1926). The adjective gaudy, however, was in use long before Gaudí was born, sometime before 1434.

 

Alan Parsons taught me all I need to know about Gaudi.