Hello folks, I came across this info. while cleaning out my old e-mail files. I recall this post was from the FJ YaHoo forum but I don't recall the author. In a continuing effort to make my FJ's run cooler in the hot desert summers I thought this may be a good idea.
RPM Randy, what do you think? Can this be done without removing the engine? I can't see how you could accurately index the cams with the motor still in the frame. Thanks Folks
Pat Conlon, Palm Desert, CA
If you take time over the winter to re time the cams by slotting the sprockets
you simply will not believe how much that picks the Yamaha 1100 and 1200 up
Both cams are extremely retarded due to emissions . this does alot of things to
include increasing the heat in the exhaust valves . springs n seats .
On the exh side lobe center angle is above 115 . Bring exhaust back down to 108 ,
intake 104 will make for lower oil temps and carbs easier to tune . Oh yeah , much much
more midrange without sacrifice in top end power .
I was doing this to mine and friends bikes back in 1985-86 and we had the king
of roll on power with smoother all-round drivability
Pat,
I degreed the cams on my '85 quite a few years ago; 104 degree intake and 105 degree exhaust. At the same time, I installed a Wiseco 1198cc piston kit, so I can't really separate the performance improvement from the overbore and the degreed cams. However, back in '01 I also degreed Hoffman's cams and he reported minimal difference in the Butt-Dyno (tm) feel.
My '85 is slightly stronger than my '93, but that could just be sprocket size differences. I personally don't think degreed cams is worth the trouble (might be worth it for racers). For instance, I've had an extra set of slotted sprockets for my '93, but I've never thought it was worth the effort to install them. Also, when I finished installing new valves in my '85 last year, re-degreeing the cams added an extra day of labor to the job.
FWIW,
DavidR.
Ok, thanks David. Were you able to dial in the index with the motor in the frame? Or just eyeball? Wait a minute, who hell am I talking to....Of course the motor was out on a bench with a degree wheel.
How are YOU doing amigo? On soild food yet? Getting your strength back or still on your follow up chemo?
You've been in thoughts, I'm wishing you a complete recovery.
Hi Pat!
The first time I degreed them, the motor was out of the frame. When I replaced the valves last year, I just pulled the head and left the motor in the frame. It's tight, but there's room to get enough dial indicators to monitor both piston TDC and valve lift. I think I have some pictures somewhere when we did Jeff's cams. It's a pretty busy photo. Yes, I did use a degree wheel, it's not something you can eyeball. Every measurement needs to be performed several times to make sure nothing is getting screwed up.
Thanks for the positive thoughts! I finished all the treatments 5 weeks ago. The recovery is in full force, although it took a while for any significant progress to begin it's ramped up nicely. I started back to work last Monday and actually began eating solid food about mid-week. Still using the feeding tube some as my mouth is still very dry and most of my taste buds are still AWOL. Mostly cheezy noodles and watery soups. Nothing spicy yet.
In a few months I'll get a baseline scan and hopefully I can maintain a clean bill of health and put this all behind me.
Take care all.....
DavidR.
Great news David! Thanks for the tips. How about this idea? Say I mark my cam chain, take my cams out and send them to someone (hint) who would install (on the cams) a set of slotted cam gears and have the cams then dialed in at their shop and locked? Then I just reinstall the cams, on the marked chain... Kinda like plug and play...
Then again maybe not. Is the FJ motor a interference design? I could see me kludging the reinstall, getting the cams out of sync and bending a valve or two, or four...
Also thanks Randy, no hurry...
Wouldn't be perfect what with manufacturing tolerances and such, the total distance between the cam centerlines and the crank centerline, the condition of the guides, and so on.
I have adjustable sprockets on mine, had to go into the motor to get a screw out (always leave the plugs in when you're working on it, now you know!), and I simply lined up the stock markings when I put it back together... it must have been "adjusted for torque" or something silly before, because I picked up a good bit in the >6k range.
Ain't broke, don't fix it?
FWIW, I asked Hank Scott this question a few years ago, and I believe he suggested putting the cams in at 107/108.
It seems to me that you're not going to gain power to speak of by playing with cam timing, but you can definitely shift at which part of the tach the power sits on. Just remember that you'll need a way to measure piston/valve clearances, if the valve is sticking down and the piston comes up you will definitely do decorative modification to things internally...
Double posting FTW!
Was digging through my notes and I found this tidbit that I'd saved from the one of the mailing lists:
QuoteDate: Mon, 06 May 1996 22:58:18 -0700
From:
I've seen a lot of discussion in the past few days about cam timing and the
duration of overlap that the factory dials into our beloved FJs. Last year I
peeked under the valve cover in search of a few more ponies. Though the
results I got were mixed, I did
record the stock valve timing before I slotted my cam sprockets. That way I
could return it to OEM specs for resale or whatever. This is what I found
stock on my FJ. The measurements were taken at .045 inches checking clearance.
In other words when
the cam moves the valve down .045" I called it open. When the cam is .045"
from no movement, I called it closed. All measurements are in degrees crank
rotation, with respect to the exhaust/intake stoke's Top Dead Center.(TDC)
INTAKE
EXHAUST
OPEN 13* BTDC 141* BTDC
CLOSE 215* ATDC 26* ATDC
LOBE CENTER 102* ATDC 108* BTDC
MAX LIFT .332" .350"
DURATION 228* 235*
TOTAL VALVE OVERLAP=39*
*=degrees
I looked around for the stock valve timing but could not find it. I remember
hearing about an article called "Fire For The FJ1100". I guess somebody
degreed the cams on an FJ and documented it but I could not find it anywhere.
(anybody seen it?) Anyway I
called Vance and Hines and they had the stock timing specs. I don't know what
lift they used for checking clearance but here it is.
INTAKE .330" lift with 228 degrees duration
and 104.5 degree lobe center.
EXHAUST .350" lift with 217 degrees duration
and 104 degree lobe centers.
If you do some quick math, that means the intake valve opened at 9.5 degrees
BTDC. The exaust valve closed at 32.5 degrees ATDC. Therefore the overlap
is 42 degrees in duration.
This was not the same as my FJ numbers but I attribute that fact to the
differences in checking clearance used and the expected variation that
comes when mass producing anything.
I slotted my cams and moved both intake and exhaust lobe centers to 103
degrees in hopes of finding a little more juice on top without killing the
FJ's natural stump pulling ability.
What I got was an engine that does okay below 4000PMs. But not as powerful as
stock. At 6500 all the way to the rev limiter she screamed! I could hit
redline in fifth (on a closed circuit course only (Ha!Ha!)) in no time at all
with stock gearing. It was still
pulling hard when the rev limiter cut in, or cut me out! The only down fall
was the HUGE power lost between 4000 and 6500. If you have ever ridden your FJ
on the highway, you will know that that is where the engine cruises. That's
what gave it the "roll-on" power that makes our bikes so much fun. I turned my
lovable FJ
into a dreadfully serious not so streetable road rocket. This summer I plan to
move the lobe centers back to 105 degrees each. I'll let you know. Oh yea, my
FJ wore a Vance and Hines Supersport exhaust system. The airbox was stock and
I was at about 1000ft ASL (above sea level). I'm wondering if anybody else
has tried this.
Pat,
how's the retirement going? :blum1:
geez not even a week yet and now you are digging into the fj for more power.
seems to me you were the biggest advocate for leaving the engine alone because it made great power and didn't need to be messed with.
The times they are a changing. :wacko3:
anyway wasn't the hot tip to use an exhaust cam on the intake for more power? :unknown:
try it you will like it.
Might be true on the 1100, I mic'd the cams on my 90, unless the duration is different (and it doesn't look like it is), the lift measures the same.....
Heh heh, quite observant Markus me lad, you seem to have put your finger on it. Alotta time on my hands. It's all good.
You were right (or I was) the 'ole FJ is just fine (for my abilities) power wise. Andy's right: "If it 'aint broke....."
I was thinking about a simple mod which, if true, would (perhaps) help the bike run a bit cooler.
Funny that you mention swapping the intake cam for the exhaust cam, it's a hot topic over at the Miata Forum.
http://tinyurl.com/mctloh (http://tinyurl.com/mctloh)
Those Russell SS brake/clutch lines work out ok amigo?
Pat
Quote from: Mark Olson on August 09, 2009, 12:29:54 PM
how's the retirement going? geez not even a week yet and now you are digging into the fj for more power.
seems to me you were the biggest advocate for leaving the engine alone because it made great power and didn't need to be messed with.
The times they are a changing. :wacko3:
anyway wasn't the hot tip to use an exhaust cam on the intake for more power? :unknown:
try it you will like it.
Thanks Andy for this info!!! Good stuff. We should ask Marsh to put this in our files for future reference.
I understand what you said about different tolerances between motors and setting up a cam gear in a shop on a FJ motor then transferring that cam and gear to a different motor would be inaccurate. I can imagine just the differences in the stretch of the cam chain between the 2 motors could throw off the numbers....
Thanks again for the info Andy and sharing your experiences, it's very helpful and enlightening.
Pat Conlon, Palm Desert, CA
Quote from: andyb on August 09, 2009, 07:45:42 AM
Was digging through my notes and I found this tidbit that I'd saved from the one of the mailing lists:
Pat,
the brake lines are bitchin, I didn't realize how spongy the old rubber hoses had gotten.
Not a lot of time to ride right now with work and the temp high.
Just celebrated my 25th wedding anniversary on the 4th. good times.
bought swmbo a new car so now she will quit complaining about me buying a parts bike and working on the fj.
good luck with the retirement and stay busy or the oprah will get ya.
Hello, Mark,
I'll be needing new brake lines fairly soon...
Russell doesn't list any FJ applications on their website.
Would you be so kind as to post the part nos. you used?
Also, did you get them locally or online, and if online, where?
TIA,
threejagsteve
Hey Steve, Mark got the Russell SS lines from me.
I took them off my '84 when I converted the front end to FZR1000 USDs: http://tinyurl.com/lxj6hu (http://tinyurl.com/lxj6hu)
I bought the Russell lines in '85, they were my first mod. on my '84. Alas, Russell no longer lists them for FJ's.
I suggest Spiegler SS lines, the ability to rotate the banjo fittings are handy: http://tinyurl.com/9ynv7 (http://tinyurl.com/9ynv7)
Expensive, yep, but after all, it's the BRAKE system we're talking about....
FYI, Yamaha strongly suggests that the oem rubber lines be replaced after 7 years....
Cheers
Pat Conlon, Palm Desert, CA
Quote from: threejagsteve on August 10, 2009, 03:36:52 PM
Hello, Mark,
I'll be needing new brake lines fairly soon...
Russell doesn't list any FJ applications on their website.
Would you be so kind as to post the part nos. you used?
Also, did you get them locally or online, and if online, where?
TIA,
threejagsteve
Thanks, Pat,
Yeah, those Spiegler lines look nice, and the price isn't so bad when you consider that Pasadena Yamaha's online parts finder says $200 & change for the OEM parts - Zanotti is likely to be significantly cheaper, but that'll probably just bring the tab down to Spiegler's range (I haven't checked Zanotti's prices yet). And OEM rubber vs. braided stainless? Jeez, I hate that phrase "no-brainer" but sometimes it's the only term that fits.
Russell does have roll-your-own lines; I'll likely price them out when I get closer to actually doing the job and see what's what.
Aside from pads and fluid, nothing has EVER been done on my brakes. They're still fine around town, but I'll completely rebuild the fronts, master cylinder to caliper seals, before I take up canyon carving again. ;)
Cheers,
threejagsteve
Steve,
Here in SoCal you can get a set made at a very reasonable price. I go tohttp://www.bakerprecision.com/ (http://www.bakerprecision.com/) in Long Beach. Take your old ones in to their shop and they will make them while you wait.
LA Mike
Hello, LA Mike,
That's about 33 mi. from me... straight through downtown, to East L.A., then through Compton... the scenic route! :o
Simi Ed also told me about a place in Northridge.
But thanks for the thought!
Cheers,
threejagsteve
Along the lines of fabricated braided lines... I got a clutch line made for about $50 including stainless ends, while I waited at a marine/engineering shop. That should expand your options a little bit.
Thanks, FJ! Yeah, I hadn't thought of checking marine applications suppliers.
And to everyone else, sorry for hijacking this thread... I didn't mean to, I just had one quick queston. :P
________________________________
To make up for it, I'll post the observation that it MIGHT be possible to see if slotted cam sprockets would be helpful by just bumping the cams a tooth along the chain - remembering that cams rotate at half crank speed, you can calculate the change by dividing the number of teeth on the sprocket by 720 (two crank rotations) to get the number of degrees each tooth changes the cam timing. For example, if there are 48 teeth on the cam sprocket, each tooth would move the timing by 720/48 = 15 crank degrees.
If a one-tooth movement provides a noticeable (and desirable) difference, then it might be worth investing in slotted sprockets to get it just right.
Warning: I'm not recommending this; just positing the possibility. If you try it, it's at your own risk, and I'm not responsible if you break your motor. ;)
Cheers,
threejagsteve
Stock cams spec to around 104/104.5 centers. 15* in either way is far too big of a change to run well. The typical range is going to be from 103 to about 108 for a typical naturally aspirated motor.
The difference between a YZ-F and the sister WR-F engines is cam timing..... one tooth on the exhaust cam. IIRC, the WR was one tooth retarded from the YZ engine. If I advance my WR cam one tooth, it'll be the same as a YZ engine......
One TOOTH on the exhaust cam.....
Quote from: andyb on August 14, 2009, 07:49:56 AM
Stock cams spec to around 104/104.5 centers. 15* in either way is far too big of a change to run well. The typical range is going to be from 103 to about 108 for a typical naturally aspirated motor.
That was just an example... I haven't counted the number of teeth on a cam sprocket, so that would be the first order of business for someone exploring the feasibility of the idea.
Cheers,
threejagsteve
Just ran across a picture of an FJ cam gear on eBay... By my count (twice to be sure), it has 46 teeth. 720/46 = ~15.652174 degrees of crank rotation per tooth.
Cheers,
threejagsteve
Is anyone looking for some slotted cam gears? I've still got the ones that carey gave me umpteen year ago.
They've got about 45* of adjustability :sarcastic:
Quote from: threejagsteve on August 20, 2009, 05:11:05 AM
15.652174 degrees of crank rotation per tooth.
THE TOOTH? YOU CAN'T HANDLE THE TOOTH!!! :sarcastic:
Not if you want to run decently, anyhow.
They're like $50, or you can kick TRoy's ass and make him send you his. Do it right! Maybe you'll be able to get his lunch money too... :empathy3:
Bumpity bump.
Cam timing;
Since I really haven't played with it in over 10 years, I am a little rusty on what I did. As most of you know, I have been racing and building Legend race car FJ1200's since 1994. I started playing with modifications with our rulebook to try and find more power.
My results were mixed at best. While I could note a better powerband per rpm range at differing settings the other end of the rpm range lost power significantly.
The most notable change I was able to make was with cars that run on a road course type track where they see higher sustained rpms. I was able to do this by widening the lobe centers of the cams. the actual degree of opening time did not seem to make much difference, but the widening of the lobe center by 2-4 degrees made a big difference at the top end of the power band before the rev limiter kicks in.
I tried to use this theory on a oval track cars, but with the wide sweep of the power band from the corner to the end of the straight, there too much of a negative affect on one end or the other.
The other issue I have had with almost all of the engines that I installed adjustable cam gears on was slippage if the cam gear on the mounting bolts. I am not sure if this was due to the abuse we place on the engine as far as the heavier weight of the car, idle to wide open, or the banging of the gearbox, but most of them slipped at one point or another.
Since most of the racers need to work on their driving skill to decrease track times, I have returned to using stock cam gears on all engine except those that have been built several times and the deck heights of all of the components are getting short. This allows me to degree the cams back to a visual center on the cam cap and I have not had anyone complain about power.
The question you posed about temperature difference within the engine based on cam timing would seem to be minimal. The core idea between the cam design & timing is to increase cylinder fill & pressure. In my opinion if you are able to increase cylinder fill with a higher volume of fuel/air your temps should actually increase.
One simple thing that I have done to every engine that comes through my door including my two bikes is to advance the ignition timing by 5-6 degrees. This wakes the engine up throughout the powerband, improves fuel economy and the engine seems to run cooler. I have gone as high as 10 degrees, but carbs and ambient temps play a major role in that application. There are advance rotors available on the aftermarket that bolt right on. In the case of the Legend car, we have to use the stock rotor. So I slot the holes of the ignition plate to the shadow of the mounting washer to obtain the timing advance.
Heat Issues;
While we are here in the Central Valley of California, we still see heat days of over 100 degrees. While this seems to be an issue that comes across the group every couple of months, I believe this is really not an issue. Imagine taking the engine, putting it in a car sideways, putting fenders and a hood over the top of it and racing it at wide open throttle on the hot summer days...
We have had to become very adaptive to the engine to obtain any type of durability from it. This engine is air/oil cooled. We have had to make the oil cooling system so large that some cars carry 6+ quarts of oil. We have air ducting running to everywhere possible to try and transfer heat from the cooling fins of the cylinder and head.
We still see enough heat on the cylinder head to soften the aluminum enough to absorb the washers under the head nuts. We have seen many times 500+ degrees of cylinder head temp at a head stud and many people see oil temp in excess of 350 degrees. Yet this engine runs that way week in and week out throughout the country.
In my opinion, the air cooling system designed by Yamaha works very well. In stop & go traffic obviously the air cooling goes away.
That is when oil cooling must take over to help transfer the heat way from the engine. This winter, I plan on designing a oil cooler system that will increase the cooling capacity of the system. My hope is to use two small fans on the cooler for those stop and go moments. The addition of the bigger cooler plus the additional capacity of the spin-on oil filter should help cool when there is no air flow.
I mounted an oil temp gauge on my bike last week and will be taking it out for a ride next week to get some base runs to document oil temps.
I have thoughts on how to make a system, and I will be making mounts & hoses that will hopefully still fit the stock application of the bike. There might be some minor modifications to be made, but by looking at my bike, I see lots of space to make it better.
Carbs;
David come up with my answers almost everytime...The only thing I have done to improve the cleaning of the carbs is the purchase of an ultrasonic cleaner. It gets the smallest jets clean everytime.
Randy - RPM
Quote from: racerrad8 on September 03, 2009, 09:19:14 PM
One simple thing that I have done to every engine that comes through my door including my two bikes is to advance the ignition timing by 5-6 degrees. This wakes the engine up throughout the powerband, improves fuel economy and the engine seems to run cooler. I have gone as high as 10 degrees, but carbs and ambient temps play a major role in that application. There are advance rotors available on the aftermarket that bolt right on. In the case of the Legend car, we have to use the stock rotor. So I slot the holes of the ignition plate to the shadow of the mounting washer to obtain the timing advance.
Randy - RPM
And no knock running on CA's 91 octane pump premium?
Thanks for all that typing, Randy -- it was very informative!
Cheers,
threejagsteve
Ok Randy that answers that....Many thanks for sharing your wisdom and experience with us!
On the ignition advance plate: IIRC Vance and Hinds used to offer a 5* (or 7*?) advance plate for our FJ's but I have not been able to locate a vendor, do you have a source? Any in your stock?
I have a 5* advance plate on my '92 and I like how it wakes the bike up...
I have been looking for a advance plate for my '84 1100 but no go so far...
Thanks again Randy...
From the FactoryPro website:
Quote
Thanks for the feedback!
Marc
--------------------------------------------------------------------------------
Feb 03,1999
Hello,
I have a 1991 Yamaha FJ1200, and saw a tech article in Rider magazine about a problem that these bikes exhibit. At low speed, the throttle is nearly "light switch" touchy on my bike, and the article said that this was normal for FJ's but there was a solution. The article went on the explain that the FJ1200 has a very sharp ignition advance curve, about 33 degrees difference from 1000 to
2500 rpm. I checked the shop manual and saw that this was correct.
Rider magazine referred to your company as one offering a fix for this tendency. I checked your website and noticed that the FJ1200 was not listed (or I didn't see it) and was wondering if you offer an ignition advancer for this bike and at what cost. Also, do you know why the factory would put such a sharp curve in the advance of the ignition? Normally this is not a problem, but at parking lot speeds it can be quite a handful, as you can imagine.
Any help you could give me would be greatly appreciated.
Thanks!
Chris D.
Well, well, there's an FJ1200 page now!
Actually, the problem is twofold - the low-end carburetion is too lean and the ignition timing curve is pretty aggressive at low rpm.
Try adding the advance and see if that's enough. Adding the Carb Recal Kit and the advance will cure the FJ's "twitchy throttle" when properly tuned.
BTW - The FJ1100 needs the carb kit before the advance - as the advance alone will cause a light pinging at cruising speed when going up slight hills on the freeway.
Thanks for the question,
Marc
I interpret this as saying you'll need to rejet before advancing it, not necessarily putting on their jetkit.
I did a quick online search and didn't turn up much, so the easy way to advance your timing may be slotting the rotor. You could pull the cover and compare what you see with ebay item 250452219541, but that looks like a late model rotor to me. Maybe you could talk Randy into trading you for one already slotted, for a fee?
Thanks for the info Andy.
I'm aware of the need for a stage 1 kit for my '84 if I run the advance plate. Makes perfect sense. The added fuel will also help the '84 run a tad cooler. Looking at the plugs I see that the factory settings are quite lean.
I contacted Factory Pro 2 years ago and they no longer had the advance plate for FJ's, hence my question.
Great idea about sending my oem plate out for slotting. If I had my choice I would opt for a set plate so I wouldn't have to worry about the plate slipping (similar to slotted cam sprockets Randy mentioned above)
Cheers!
Pat
<edit> I see that the eBay item is for the 84/85 FJ1100, Thanks Andy! I'm on it.
I have not heard any on mine. My wife on the other hand, while she is still learning, tends to lug the engine. I can hear on the low speed lug that she is putting on it. That tells me I need to richen the pilot & needle circuits in her carbs. I am running 117.5 jets in my carbs with the stock needle raised .020. I am at about 70 above sea level here, but we ride up into the sierra's ever week beyond 5000 feet without issue.
Randy - RPM
The one Andy has noted is the early model with the dual pickup coils. The later model single pickup system uses this rotor; 150369874295 which is currently on eBay.
There is not chance of the P/U plate moving once it is mounted. The is nothing that is putting tension on it like the cam gear is trying to turn the cam.
Randy - RPM
I believe they're only referring to the 1100's when they said that, not the 1200.
When reading the plugs on the FJ, make sure that you're reading them right.
http://www.strappe.com/plugs.html (http://www.strappe.com/plugs.html)
Quote from: Pat Conlon on September 04, 2009, 01:59:45 PM
<edit> I see that the eBay item is for the 84/85 FJ1100, Thanks Andy! I'm on it.
Pat,
Call me! 972-sixonetwo-zero9three6
DavidR.
All the big-bore bikes of this era were way too lean on the idle and off-idle circuits. The factories did it for emissions.... the big-bore bikes don't use the other carb circuits during the EPA testing, so they left the mains and lower sections of the needles at a properly rich setting.
I have put #40 pilots in my '90, as well as the DJ air correctors and needles/main jets(114, IIRC). My mixture screws are all around (the ideal) 1 turn out and she runs GREAT! :biggrin:
Rich, what are you running for pipes? Still stock, or 4>1?
TIA,
D&D.... 4-2-1, and a UNI airbox insert. Stock airbox with a lot of holes in the cover.