The Really, Definitely Completely Un-Authorized TBS

[Auron]

I did this as well and it totally transformed the bike. Probably saved me from having to sell it. Thank you so much for figuring this out. Now someone just need to figure out how to adjust them whiile riding it!

 

[Fred W]

I'm really glad that this helped you guys out..

Ride on!! :scooter:

 

[NBB]

Well, last night I finally had the chance to do the TBS. I was surprised at what I found. First I managed to set up the fuel tank next to the bike so I had lots of room for adjustments. The bike now has about 1300 miles on it. All the idle adjust screws were set the same at 5/8th of a turn. The hot idle was nowhere near perfect. I went ahead and closed them all and reset the idle rpm to 1000rpm. I could see that the base ballance was way off. I went ahead and revved the bike up in neutral to 4000 rpm and found that Cyl.# 1 and 4 had a lot more vacuum than 2 and 3. Now comes the kicker. In one of my last posts on this thread, I was talking about loading up the engine (like I was riding down the road, since nobody cares if the butterflies are ballanced when revving in neutral)and seeing what kind of vacuum I was getting then. I found it easiest to leave the bike in second gear and rev it up to 4000rpm. Then I applied the rear brake and gave more throttle and kept the rpm to 4000. The numbers were way different than when revving in neutral. I reset the throttle bodies the best I could. The rear brake was overheating by the fourth pull, so I need to cool down the rear brakes with a water spray next time I do this. I reset the idle adjust and rpm when all done. I also installed a Audiovox cruise control so once I get the necesary vacuum hose needed to finish the install, I can take it for a ride.

I would love to see someone do this TBS on a dyno. I hope someone else will try the same procedure in order to confirm or negate my findings.

I did the TBS earlier this year using this method of loading @4k RPM in 4th gear, and noticed the same initial readings of cylinders 1 & 4 being higher in vacuum than 2 & 3 with a Morgan carb tune. We noticed nearly the same readings on another members FJR at the MN tech day this spring ans his ride had nearly 98k miles when the TBS sync was performed. A couple of weeks ago we rechecked his bike (now with almost 120K) and only cylinder 1 had changed ( at 4k rpm) and that was not much more than 1 bar difference. However the idle vacuums were off a bit more.

-K

 

[Fred W]

I went back and edited a couple of my earlier posts where I was doing some thinking out loud about how effective this RDCUA TBS procedure was going to be, and reading it now may have cast doubt as to the effectiveness of the procedure. As noted now in post #1, I really am convinced that this results in the best case TBS throttle plate alignment and is the easiest way to perform it.

 

[TomInPA]

I went back and edited a couple of my earlier posts where I was doing some thinking out loud about how effective this RDCUA TBS procedure was going to be, and reading it now may have cast doubt as to the effectiveness of the procedure. As noted now in post #1, I really am convinced that this results in the best case TBS throttle plate alignment and is the easiest way to perform it.

I was a bit saddened to see how many times negative votes have been bestowed on me throughout this thread. :huh: Sometimes I just don't get people. :glare:

I guess this is proof positive that no good deed ever goes unpunished.

Fred, I undid about 5-negative votes for ya. You must have attracted a rep-assassin somewhere. Anyway, I appreciate the work you did on developing the procedure, and it's what I've been using on my bike and other friends I helped to tune their bikes. Illegitimi non carborundum.

 

[mavrik]

I went back and edited a couple of my earlier posts where I was doing some thinking out loud about how effective this RDCUA TBS procedure was going to be, and reading it now may have cast doubt as to the effectiveness of the procedure. As noted now in post #1, I really am convinced that this results in the best case TBS throttle plate alignment and is the easiest way to perform it.

I was a bit saddened to see how many times negative votes have been bestowed on me throughout this thread. :huh: Sometimes I just don't get people. :glare:

I guess this is proof positive that no good deed ever goes unpunished.

if there were not individual pioneers and thinking outside the box...we would never be able to grow as a forum and/or even as a society...nay sayers will always be around, but very few actually put the efforts in to help others

 

[Fred W]

Thanks guys.

I wasn't really fishing for compliments or + votes, just really am surprised at some people's reactions to other people's posts. Not just in this thread either.

By the way... I wonder if people would do that if they knew that the admins can see who placed the votes?(and no, I'm not an admin)

 

[Bugman]

Good Post! :clapping: Now I just gotta do it.

Ya got me wondering about the negative votes. I think you get only one a day. I would think the technical stuff would get voted up while the never ending pointless stuff would be voted down. Go figure...

Fuelinjectiti non carburetor

 

[ABQFJR]

This thread is pure gold.

Probably my single biggest complaint with the FJR has been the buzziness of the motor. I did the authorized TBS back in the spring and didn't notice any difference... now I know why.

I can't wait to get home and try this.... OhBoyOhBoyOhBoyOhBoyOhBoyOhBoyOhBoyOhBoy.... :crazy:

 

[wheatonFJR]

This thread is pure gold.

Probably my single biggest complaint with the FJR has been the buzziness of the motor. I did the authorized TBS back in the spring and didn't notice any difference... now I know why.

I can't wait to get home and try this.... OhBoyOhBoyOhBoyOhBoyOhBoyOhBoyOhBoyOhBoy.... :crazy:

Remember...this TBS is really, definitely, completely Unauthorized. If you're motor blows up good...it's on you.

 

[ABQFJR]

This thread is pure gold.

Probably my single biggest complaint with the FJR has been the buzziness of the motor. I did the authorized TBS back in the spring and didn't notice any difference... now I know why.

I can't wait to get home and try this.... OhBoyOhBoyOhBoyOhBoyOhBoyOhBoyOhBoyOhBoy.... :crazy:

Remember...this TBS is really, definitely, completely Unauthorized. If you're motor blows up good...it's on you.

Indeed, the "unauthorizedness" of this procedure is what makes me think it's really worth trying. Additionally, I'd be interested in learning how dorking this procedure could blow up the motor.

It WOULD be an easy way to convince the wife to let me go get a 2013, though. "Baby, the really smrt guys on the forum said the 2nd-gen was garbage and look, they were right!" Hmmmmm....

 

[ABQFJR]

Well, I got some time to tackle this on Saturday night. The throttle plates were definitely a little out of sync, though not by much. The biggest variance was between cylinder #'s 1 and 3, about 20mmHG between those two:

After about 1/2 hour, I was able to get the readings much closer. Yes, it took awhile, because I'm a perfectionist, but I had to settle for "close enough" this time:

It's too early to tell how big of an improvement this has made, but on a quick trip around the block after the synchronization, I'd say it DID seem pretty smooth. Smoother than before? Like I said, it's hard to tell. I'll report back once I get out on a decent ride.

Also took the time to put the charcoal canister back on the bike while I had the tank up. I know, I know, the usual mod is to take it off (which I did, previously), but I was getting tired of the garage filling up with fuel vapors after every ride.

 

[Constant Mesh]

Need an explanation for something I noticed.

I closed the air screws and then adjusted the idle knob for a 1100 rpm idle. Then I synced the throttle valves. Everything's fine.

Then I raised the idle to 1500 rpm (open the throttle valves a bit) with the knob. TB4 didn't change but TB1 and TB2 were no longer synced. I didn't continue but I'd guess if I had raised the idle another few hundred rpm the sync profile would have changed again.

I can only assume that syncing the throttle valves at one position doesn't really guarantee they'll be synced at another position. I've noticed that before indirectly. If I sync the air screws, ride a bit, and then change the idle a bit with the knob, the air screws sync is scrambled. A small movement of the throttle valves changes the air screw sync.

The butterfly throttle valves don't offer very precise flow control. When they're almost closed a small movement can yield very different flows.

 

[Fred W]

Need an explanation for something I noticed.

I closed the air screws and then adjusted the idle knob for a 1100 rpm idle. Then I synced the throttle valves. Everything's fine.

Then I raised the idle to 1500 rpm (open the throttle valves a bit) with the knob. TB4 didn't change but TB1 and TB2 were no longer synced. I didn't continue but I'd guess if I had raised the idle another few hundred rpm the sync profile would have changed again.

I can only assume that syncing the throttle valves at one position doesn't really guarantee they'll be synced at another position. I've noticed that before indirectly. If I sync the air screws, ride a bit, and then change the idle a bit with the knob, the air screws sync is scrambled. A small movement of the throttle valves changes the air screw sync.

The butterfly throttle valves don't offer very precise flow control. When they're almost closed a small movement can yield very different flows.

What you have noticed is what I expect the minor pitfall of this adjustment method is (or has been all along) and that is...

When the throttles valves are nearly closed at idle (1100 rpm) any even small amount of crud built up on the faces of those butterflies will have a rather significant impact on the flow, and therefore vacuum , at that minor opening. As you open up all four butterflies (mechanically tied together) that crud will become progressively less significant, and the actual angle of the butterflies will be prevalent.

The premisses of the adjustment is that by adjusting the tiny crack of an opening at a very low throttle setting (assumption of clean or identically dirty throttle plates) will set the throttle plates perfectly parallel to each other, but that wouldn't be true if there was a buildup of spooge on the leading edges of some plates and not others.

What I'd suggest, as both an experiment and a corrective action, would be exactly what I intend to do in the next week or so on my bike; To clean the throttle bodies with a spray type intake cleaner (I'll be using the spray SeaFoam product) and then recheck your results. I have a good feeling that you'll see that the variability with throttle opening becomes lessened if not eliminated.

FWIW, I also intend on also going through a full seafoam combustion chamber de-carbonization, as my poor old '05 is coming up on 75k miles, and I want an accurate measurement of the valve clearances when I go in to measure them. So that may contaminate my vacuum results when I get around to actually measuring them afterwards.

Good Luck!

 

[ABQFJR]

Fred,

Happy New Year! I was just wondering if you had had the chance to perform your cleaning experiment, and if so, if it affected your sync values at all. I haven't really had my bike out for a good ride since I did the sync (I know, I know, I'm an unworthy owner), but I'd be very interested to hear what your findings were.

-Dustin

 

[Fred W]

Yes, I did do the full seafoam treatment, but it was right before I adjusted my valves, so I'm not sure if any changes to the sync were from the cleaning or the intake valves now being open less (larger cam clearance). The intakes all required adjustment, but the exhausts were all still the same as the prior two measurements. When I got done with it all the engine is now running smoother than it ever has, at least that I can remember.

I haven't had my bike out much either since those adjustments, but that is more because of the frigid New England temps and the nasty white stuff on the ground than anything. I typically will subject the V-strom to the winter salt rather than the FJR.

 

[odot]

I went back and edited a couple of my earlier posts where I was doing some thinking out loud about how effective this RDCUA TBS procedure was going to be, and reading it now may have cast doubt as to the effectiveness of the procedure. As noted now in post #1, I really am convinced that this results in the best case TBS throttle plate alignment and is the easiest way to perform it.

I was a bit saddened to see how many times negative votes have been bestowed on me throughout this thread.

Sometimes I just don't get people.

I guess this is proof positive that no good deed ever goes unpunished.

Man, no wonder my tbs went from bad to worse.............Now yer really gonna get some negative votes!

Just kidding.....I've only had a tbs done once on me skoot. I can't find it in myself to give a shit about a small variation in carb suction.

 

[Chiefblueman]

I went back and edited a couple of my earlier posts where I was doing some thinking out loud about how effective this RDCUA TBS procedure was going to be, and reading it now may have cast doubt as to the effectiveness of the procedure. As noted now in post #1, I really am convinced that this results in the best case TBS throttle plate alignment and is the easiest way to perform it.

I was a bit saddened to see how many times negative votes have been bestowed on me throughout this thread.

Sometimes I just don't get people.

I guess this is proof positive that no good deed ever goes unpunished.

Man, no wonder my tbs went from bad to worse.............Now yer really gonna get some negative votes!

Just kidding.....I've only had a tbs done once on me skoot. I can't find it in myself to give a shit about a small variation in carb suction.

Odot, it's not your tbs that will give you trouble. It's your battery.

 

[odot]

You have no idea how right you are.

 

[ABQFJR]

Well, I finally got a chance to get the bike out for a decent-length ride yesterday, and was disappointed in the lack of improvement in my buzziness situation. I spent some time re-torquing engine mounts with a similar lack of success. I went back and read through this entire thread again very carefully, and I believe I may understand now why the procedure didn't work so well for me. In short... I screwed it up by not adapting it for the 2nd gen nature of my bike.

I did the procedure without checking the balance a higher-than-idle RPM, load or no load. I think that is where I messed up.

Pretty much all of the discussion here has revolved around the 1st gen bike, which has a different way of setting idle speed, correct? When you close down your idle air screws, you're basically choking off all your air bypass (except for what is allowed by the throttle plates), right? IIRC, on the 2nd gen, the idle adjustment controls another air bypass that functions even when the idle air screws are all turned completely in. On the 2nd gen, adjusting the idle back up to 1000 doesn't actually open up the throttle butterflies at all, as it does on the 1st gen, right? I suppose what I'm trying to say (or rather, ask) is: On your 1st gen bike, with the air bypass screws closed, and your idle adjusted up to 1000 RPM, your throttle plates are open more a bit more than on my 2nd gen bike under the same circumstances, correct? Or am I way off base here?

There is, of course, the likelihood that my intake balance is fine and the buzziness is being caused (perceived) by something else... perhaps that mushy thing between my ears.