not idling down sometimes.

[blkryno]

I have a problem on my 81 11 SH. The bike runs great at all other times its just sometimes after I run at highway speeds for awhile when I exit and come a stop
it does'nt just come down to idle speed on its own. If I hold the front brake and let the clutch out a little she will usually then come down to idle speed but sometimes I have to do it a couple of times. I've been through the carbs, jets, needle and seats float height,the vacuum pistons seem to slide freely and eaislly, then back on the bike adjusted and syncd, new vacuum lines and caps on the carb boots, boots are good no cracking or splits, timing is right on the mark. After warmup it idles at about 1100 rpms.The bike sat for a long time so when I went through this bike with you guys help I did have to replace the #3 carb and I got that off a rack right off another 81 SH, carb #s match. Like I said it does'nt happen all the time just irritating and kinda embarrassing when ya pull up to a stop with other bikes. Now having said all this I still think its something in carbs that I'm missing.

[motoman]

JAT....additional heat created from a good steady run may be tattle-tale sign of a bit too lean. Cam chain adjustent may be allowing somewhat loose chain throwing cam timing off a tad and givng it a hang idle when hot.....again lean. I just mentioned the latter as I can remember back when mine was new, it would start doing that....doing the chain adjustment would have it back to normal. Lest that was a telltale sign of needing done for me back then, not knowing any other of the bikes quirks.

[Hippie_Dave]

Totaly agree, too lean will make them idle crazy high when good and warmed up. If richening things does not seem to change anything, I would check the cable, the throttle housing and the linkage on top of the carbs. I have had that linkage cause some hairy situations out on the road. Just my eight cents worth.

[blkryno]

You guys make a lot of sense about the too lean situation I've been wondering about that too. Because I've been getting a little back firing on deceleration at times but not much. Back in 81 about 2 months after I bought this bike the cam chain snapped at 55mph on the freeway. That seized up the motor and back wheel I remember now pulling in the clutch and that freed up the back wheel and kept us from going down. The dealer did right by me pretty quick and I still have slash marks in the cam cover from the chain slapping around. So I make sure that chain and tensioner are right every season. So I think the too lean situation is the place to start. I've got a colortune I just didn't think about using it till you guys said something here. I think I heard that these bikes like to run a little lean but I'm probably out a little far. I'll check it this week. Thanks

blkryno

81 11 SH
79 11 SH

Semper Fi

[motoman]

Might SERIOUSLY consider swapping out that manual adjuster for a Auto adjuster that won't back off when front side of cam chain is "loaded". Don't think a dealer will cover you second time around if the unknown slack takes a hop a tooth or so..........

[blkryno]

Yeah I've been noticing in different posts something about a cct off a venture. What info do I need so I know what to look for? How much should I be looking to pay ? As long as I'm asking questions I been wondering about some the other stuff I've noticed.
Tkat fork brace ? did read a few posts about that.
XS 750 Final Drive ?
Brass carb floats ?
Drilled out airbox ?
I think I read something about a big bore kit (I might have that wrong.)
So am I missing out on something good here. My bike is totally stock right down to the original tool kit and yellow wheel lock chain and in very good condition. So is this stuff a smart add on or something to consider when replacing parts after wear and tear or part failure ?

blkryno

81 11 SH
79 11 SH

Semper Fi

[DGXSER]

Some of what your asking is pure opinion stuff, so your bound to get different feedback. I'll give you my thoughts on each...

Yeah I've been noticing in different posts something about a cct off a venture. What info do I need so I know what to look for? How much should I be looking to pay ?

The CCT off of several models will work, some are straight bolt on, some need a little filing of a hoel to fit. The Venture models both 1200 and 1300 are straight bolt on. There is a list of the others here somewhere, I think the V-Max are also bolt right up. The Vision ones I think need some filing. This modification falls into the category of fixing a bad design with a better one and I would recommend it to anyone.

Tkat fork brace ? did read a few posts about that.

A few resent post will give you alot of good info on this one.

XS 750 Final Drive ?

This is in the tech tips. It is not a fix for a bad design necessarily like the fuse box and the cam chain tensioner. This is more a matter of feel and comfort so to speak. The XS750/850 is close to a bolt up change. It changes the final gear ratio for the bike and lowers engine RPM for the same speed. The majority of folks who have made the change love it, some nay sayers are among the crowd.

Brass carb floats ?

Brass floats were used on the 78-79 model year carbs. They are not an upgrade, and in fact, many people have bought the plastic floats that are in your carbs as an upgrade from the brass ones.

Drilled out airbox ?

One way to increase air flow into the engine, drill holes in the bottom of the airbox in the center portion of the air filter (inlet area so all air is still filtered). It can increase engine performance. I have never done it myself, but I am more of a cruiser than a corner carver.

I think I read something about a big bore kit (I might have that wrong.)

A company called WISECO makes a kit to increase engine displacement by boring out cylinders and replacing the pistons and rings. Two kits have been available, not sure if they are both still offered.


And BTW, the 79 model year would be an F or an SF. the S indicates a Special versus a Standard model, the F is for the model year. 78 = E, 79 = F, 80 = G, 81 = H. And the midnight special is the LG or LH model for 80 and 81 respectively.

[motoman]

My is totally stock right down to the original tool kit and yellow wheel lock.// That said, I take that as being a Venturer you have. Your showing it's a Special. The auto-tensioner can be had from a Venture/VMax or 550Vision. Top hole of Vision one has to be filed(elongated) a bit for hole match. Gearing choice of the final drives is kind of a personnel preference thing. If your plannin' on doing alot LD rides on the slab the 750/850drive would cut back the cruising rpm substantualy. Either way works fine. Brass floats no worky in those later carbs. The fiber ones in your later model carbs are just fine. TKat fork brace WILL give bike a quicker response and more predictable.....and help to a certain degree the front tire from erratic wear patterns. And if your bike is an 81 Standard and not a Special, replacing that one carb off a Special leaves you with a mis-match set-up..........The 81 Standard and 81 Special had different metering rods!!! No big bore unless its necessary ,IMO. With all else stock, leave the air-box alone, no mods....again,IMO. Hope that helped...

[blkryno]

Thanks for the good info guys. I was ignorant of the year and letter designation.
Did seem to me there were a lot of different models when I would be looking at other posts. That's why I come to this site cause there's a lot of things I can learn. I do feel I need more info to find the auto cct from one of these other models. I mean if I'm poking around the bone yard having a minds picture of the bikes to look for would help. Or is there new cct to be bought ? I kinda like the sound of the 750 final drive though. I really do have an 81 and a 79 Special I just had the letters wrong here are some pics I took today:

http://s203.photobucket.com/albums/aa75/blkryno/

blkryno

81 11 SH
79 11 SF

Semper Fi

[bikerphil]

Those are both nice bikes. It looks like that 79 is going to get chopped, .

[CaptonZap]

Howdy,
Here's another thing to check.
I have an 80G, which, when I got it running after a 12 year rest, had the same symptoms as yours.
When I took the carbs off to clean them, I discovered that the bottom Allen head screw that holds the rubber connecter on number three to the head was missing. Took the connecter off, daubed a bit of Gasachinch on it, put both bolts back in, and have never had any trouble since. Evidently, when it got hot, things expanded enough to allow some air leakage.
Let us know what it is, when you figure it out.
CZ

[Tropic-al]

Hey ryno.

Check your advance plate. It is supposed to have 2 springs and they need to retract once they are moved.
Sometimes the springs are bad, missing one or just need a bit of grease in the shaft to be able to move freely.
When the plate does not return it idles high until you correct it by releasing the clutch.
Hope I'm explaining correctly.

[motoman]

No mechanical advance(springs/weights) there Trop.......all mechanical advance done through the TCI. BTW......damn nice example of an unrestored 81 Special!.......and forgot the Special also had the lock/chain also in 81'. Run athird of can of Sea-Foam with that Special tank fueled full through it....see if it corrects itself.....would'nt hurt to do anyways.

[motoman]

Google typing in pics and specs. of 83 and up through 89 I believe(pick one year for googling), same procedure for Vision550 for pics. Go to your local salvage and jack...er purchase one. Just a hint if taking one off a Venture, Remove the one from the back paired cyls.....nothing in the way, but having a 5mm Alen socket and ratchet with ya will take you all of one minute to remove. You'll NEED the allen bolts with it otherwise you'll have to shorten the originals (bottom holes). Gotta remove the Air-box/carbs to get to the front paired cyls. tensioner. Lest that's the set up on the Venture and V-Max. Once removed, take center bolt and sealing copper washer off the front, remove the spring, rock the spring loaded locking piece back off the slots and push the piston back in leaving the bolt/spring out until installed on the XS11. Install spring and retaining bolt, your done.......but PRIOR to removal of Eleven's tensioner follow procedure shown in the tech tips or threads here pertaining to process. MOST importantly, bike HAS to be on centerstand. Other than that, following simple procedure WITHOUT removing valve cover is only a ten minute job, and could very well save your scoot from having valves kiss pistons. Some have had issues with timing jumping and damaging valves......but IMHO, don't ALWAYS hear the WHOLE story. If you follow the procedure to a T as if you were going to do the manual cam chain adjustment.......except your removing the old tensioner instead, not an issue, lest I haven't had any and I've done it five times so far. Let us know here if you have any question on the procedure when you get the Auto-tensioner.......only dum question was the one not asked...........

[blkryno]

First let me respond to the most important concern. bikerphil don't be to sad about the 79. I appreciate the original look of these machines so much that my plan is to do nothing that can't be turned back to the original 79. Actually it came to me with a 4 in 1 exaust and I did find a couple of original exhausts sets, one chrome and one black from a MNS. They both have their share of dings seeing as both bikes I got them from were crashed but they are solid all around. After cleaning them up and maybe some hi-temp paint I think they will be usable and not look to bad. But of course who knows exactly how they are inside. My idea is to do as much of this from boneyard parts as possible like if I want to cut down a fender I'll get another one from the boneyard any original part I take off gets cleaned, wrapped and put on the shelf. Like with my 81 the only OEM parts I don't have I think are the original tires and I had to repaint the tank and side covers.Here's a suggestion for anyone going to have to store a bike for a long period is take off the tank and side covers and bring them in the house, wax them on occasion. If I had done that I probably would not have to paint them. They were always in the garage but the hot summers and cold winters over the years just made the paint crack off. The 81 is my total stocker and for when the wife comes with and the 79 is going to be when I want some ME time, as they say.
Motoman thanks I'll google the models.
I've used seafoam for a long time on all the motors around my place. When I put stuff up for the winter I always add a good dose in the tank and run it till I'm sure the mix is in the carbs it works as well and keeps things cleaner than fuel stabilizer IMHO. Another good product to use when you really need to clean stuff out is called ring-out. An old repair guy around here had me run a bottle of it with a tank of gas through my 81 after it sat so long it cleaned out most of the old fuel shellac and grunge that came from sitting for years. I'm going to richen up the fuel mix next I think that has a lot of merit. Like I've said been through most everything else. Yesterday was a very hot day here 96 degrees (hot for MN.anyway ) and it ran along really well and only did the revving occasionally.

blkryno

81 11 SH
79 11 SF

Semper Fi