Gearhead

Sorry about the “two thread” thing. I just wanted to give some closure on the rubber plug thread in case somebody reads it some future day looking for answers about those little buggers. UPDATE: This morning I pulled the plugs, checked out the plugs, caps and wires and ran compression. - Plugs look fine, they should because I had them out recently. Checked resistance of the plugs from connector to center electrode; all were between 4.0 and 4.6 k ohm. I may replace, but am betting money that won’t fix my problem. - Caps also look fine. I found my record of when I took them apart, cleaned, put together with silicone grease for corrosion protection. It was many years and 50k miles ago, but the grease worked as there was NO corrosion anywhere. Resistance across the caps measures same as it did in the past: ---- 1 and 3 are factory caps and measure 8.6 and 8.8 k ohms. ---- 2 and 4 are NGK replacements and measure 4.7 and 5.6 k ohms. ---- I don’t know why the fronts were replaced but not the rears. It's always been that way while I've owned it. - Compression is good and the most consistent of any engine I’ve ever tested. I had all plugs out, carbs drained and fuel pump unplugged, headlight fuse out, battery on a charger to keep fresh, and throttle open, engine cold. Ran each one several times to verify and the results were within 5 psi every run. I recorded the psi registered at 5 strokes / 10 strokes. ----1 – 180/195 ----2 – 180/195 ----3 – 185/200 ----4 – 180/195 I didn’t check the timing yet, but I will when I put the plugs and caps back together. So far this is telling me the engine mechanical and spark are fine, which makes sense because they were fine when I tore it down 3 years ago. Good advice, need to do these. More thoughts on the carbs, since those are the only things that changed since I tore it down. I have one slightly wonky float, need to address that, but all 4 carbs are acting up so I don’t think that’s the whole problem. I’m wondering about the Coasting Enrichers. Other than cleaning and some new parts installed, disabling those is the only thing I actually changed in the carbs (did so because 1 or 2 of the diaphragms were compromised and they’re spendy). As I’ve said, everything I’ve read says they ONLY come into play under the very high vacuum of throttle chop deceleration, and only briefly, to enrich the pilot circuits under that condition to prevent lean misfire and exhaust popping. But what if that’s not accurate? Maybe they also “enrich” at standard idle vacuum…and if so, disabling them would cause my lean problem. I took a chance by disabling them, maybe it bit me. I think I can test this pretty easily. The diaphragms are the only part of the carb easy to access with them on the bike, and pilot air jet #2 is under the diaphragm. (Pilot air jet #2 gets closed off when the Coasting Enrichers engage.) I could easily plug those with toothpicks or something similar – something temporary – in about 20 minutes. Then I could run the bike and see if the pilot circuits and idle behave normally. Seems a good experiment. Patch, to address more of your questions and excellent suggestions: Please ‘splain what you mean I have not done this precisely in the manner you described. However, I have the following evidence to tell me they are good. - They were balanced before. - I didn’t change the adjustment screws when I disassembled the carbs. I did, however, split the rack which affects the physical relationship and adjustment. - I did take a good look at the throttle butterflys after reassembly and they were all sitting about the same in the bores. - When I balanced them with the mercury sticks after reassembly, twice now, they only required small adjustments which tells me they weren’t far from where they started. - I believe this is the factory specified way of balancing carbs, which I’ve done successfully on a number of bikes. When I disassemble them for the third and final time, I can use a feeler gage to ensure they are set the same before reinstalling them. QUESTION FOR YOU: Are you saying you ONLY bench set the butterflys, and do NOT fine tune them by vacuum? Evidence of lean pilot: - Many turns out required on pilot screws. - Stumbles when first given throttle, then takes off. - Choke (enricher) greatly improves the condition. - Condition gets gradually better as engine warms up, with it almost normal when engine is very hot. That said…I haven’t fixed it yet so all possibilities are on the table! Correct, I checked by the spray method with engine running. Correct. And correct. Please ‘splain. I understand the potential for high compression readings, but not the rest. Well, I don’t hear any pinging which I normally detect by ear, plus now we know my compression is consistent and I would say in the normal range. This just keeps getting more fun…Thanks! Jeremy

Patch, in response to your questions you posted on the "rubber plug" thread: Are you saying that you went thru the carbs as we mentioned, completely and the bike still won't hold idle without the choke or transition smoothly past a 1/4 throttle? More or less, yes. It will idle, but with pilots WAY out. Do you know how to check the timing? Yes. I'll do that when I check out the ignition stuff. What on my original symptoms has changed? Nuthin!

Hey Patch, I'll respond to this over on the main thread.

UPDATE 2019-07-29: 1) Took it all apart again, found nothing noteworthy. Double-ensured everything was clean, especially the pilot jets and full circuits. I took the time with a carb in hand and the flow diagram open on the bench, and ensured that when I sprayed carb cleaner in the correct hole at the jet block surface, it came out in full streams from the pilot feed holes in the throttle bore. This includes the hole that the pilot screw adjusts, as well as three holes in a small pattern under the edge of the throttle plate when it's closed. 2) Rubber jet block plugs were swollen with fuel, probably not leaking. I treated them and the needle jet o-rings with wintergreen oil which made everything supple again - magic. 3) Replaced jet block gaskets 4) Note that the Coasting Enrichers are still disabled, vacuum passages plugged up, as before. 5) Put it all back together. No change to symptoms. Re-synced carbs and re-set pilots, similar to before, 3 to 5 turns out and still too lean. 6) Checked fuel levels and 3 of them are fine, 16-17mm below the line (spec is 15.5 to 16.5). Carb#4 fuel level is erratic and on the low side when idling, varying from 17 to 20mm below the line. This is new to me. Sometimes it creeps up and down slowly, sometimes quickly. Have you guys seen this before? What causes that? The carb vents are clear. Maybe a sticky float? What would it stick on? I haven't yet checked the compression and plug wires / caps, will do that next. The erratic fuel level is definitely something I need to check out, but I don't think that's my full problem because all the carbs need their pilots set very rich for best running. This is quickly passing the frustrating mark. I'm not normally one to give up on this kind of stuff, but I'm getting this bike ready to sell. I may soon be at the point of cutting my losses and selling it as-is. ARGGHH. If you are following my saga, thank you and I value your continued feedback! Thanks! Jeremy

Update on rugger plugs: I soaked them per post#2 and it worked - the plugs are normal size and rubbery again, fitting snugly. That being said, I also noticed when I disassembled that they were already snug in the holes, so being immersed in fuel swells them as well. But the wintergreen oil soak did work. However, this did not fix my problem with the pilot circuit. Full carb story: https://www.venturerider.org/forum/showthread.php?141445-87-VR-carb-problem

Update: Been busy on other stuff, plus had to order jet block gaskets and wintergreen oil. I did the wintergreen oil / alcohol soak trick on the stiff rubber jet block plugs and needle jet o-rings, and it worked as advertised. Truly impressive, the softening and slight swelling effect. Now the plugs fit snug. I have the carbs stripped down, haven't done anything else with them yet. I did re-check the jet block on one, removing the idle jet and emulsion tube, found nuthin'. I should get back to them soon. I'll re-check the pilot passages, then reassemble with new jet block gaskets and good-sealing jet block plugs. Check the compression and plug wires / caps. Man, I hope that does the trick. I'll let you know. Jeremy

EGR? You sure about that? Where's the EGR on a Venture?

Thanks again guys. I may not get to this until the 4th. But some good stuff to check. Regarding high tension spark problems, I'm with Patch, they generally happen at high throttle conditions, and when I whack it in the mid or upper range it really scoots. So I don't have a lot of hope there, but I can look. I think I've looked at the wires and caps before, but I've put 80k on the bike, so....

Thanks Puc and Patch. I have torch tip cleaners. But I've also read that they can scratch the bore of a brass jet and that can affect the flow metering properties. I could try them gently. It's just that I've done a fair number of these before, and I've seen plugged jets, and the light thru the hole in the center looks either funny or non-existent. That said, I have the carbs stripped down again so I can double-check and gently try the tip cleaners. I ordered new jet block gaskets as well, and will re-rubberize the plugs. I did the thing where I sprayed carb cleaner in the idle jet hole, but I'll do that again also to ensure it's getting thru the two holes in the carb bore by the throttle plate. It's weird to me that all 4 carbs have to be set with the pilots extra far out, 3 -5 turns, where before it ran best at 1.5 - 2 turns. I did the TCI relocation to the top of the airbox years ago, I can check that connection. And I'll check the compression and plug wires. Again, it's hard to fathom that the problem is anywhere other than the carbs because I didn't touch anything else, the fuel was drained, and it sat in a benign environment. I'll keep at it. Thanks again. Jeremy

Hey Patch, I did a carb sync by vacuum with a set of carb mercury sticks once the engine was warm. Set the idle to 1000 rpm. Does this not accomplish the same?

What setting are referring to? Fuel level? That is right on spec. First post has a detailed description of the bike's behavior, but to summarize: Choke does in fact solve all the problems, so I know it's lean. When it's kinda warm it will idle w/o choke, but remember I have the pilots out 3-5 turns which isn't right. And it doesn't take initial throttle very well, a little stumbling. When it's "good n hot" it almost runs right, but still doesn't quite respond correctly right off idle, you feel this when taking off from a standing stop. Mid range and top end are great. I'll check compression when I can. Thanks Patch.

Update: I pulled the carbs back off and stripped them down. The black rubber jet block plugs had been hard and loose-fitting, I was going to recondition or replace them as discussed in a separate thread, thinking this was likely my problem. But when I got in there I found that the exposure to fuel has made them swell and get softer, such that they now fit snugly in the jet block holes. I'll still do the wintergreen oil reconditioning, but I don't really think they were leaking. I pulled the jets out of one of the blocks and verified that they are still clean and clear, along with the jet block itself. I found that I had apparently neglected to tighten the brass screw that secures the needle jet to the jet block in one carb - DOH. Not good, but I don't think that accounts for my entire problem. Jet block gaskets - as I said before, I didn't replace them. I've generally had good luck reusing such gaskets as long as they go back precisely where they came from, which these do because they are stuck to the jet block, and there are precision alignment features. But since I'm running out of candidates for the cause of my problem, I'm thinking I need to get new ones. Spendy lil buggars. I thought about trying to make them, but that sounds...taxing...they are pretty precise. Pilot air jet No 1, Manual p5-6 Note 16 - I had these (and all the jets) out. Sprayed a ton of carb cleaner and air through the passages, and cleaned the jets, sighted thru them to a light source and verified that the hole in the jets is round and clear. I haven't done anything with the compression or rings. I can check the comp, but it was fine 3 years ago, and it has sat in my insulated, fully enclosed garage with the carbs removed, so I have a hard time believing something changed there. So....what else to look for while I'm back in the carbs? Thanks, Jeremy

Hey Patch, Page 5 - 6 etc of what document? The pilot air jet is the 170 size jet under the slide diaphragm, yes? They're fine. I took the carbs COMPLETELY apart and cleaned everything. And they really weren't dirty to begin with, since this bike never sat unused except after the carbs were off and drained, so there was literally NO crud found in there. I realize this is unusual. I ordered some Wintergreen Oil, and I'm gonna re-rubberize the plugs (and the coolant plugs on the sides of the block) with that Wintergreen / alcohol mix. I don't have the oil yet, but maybe I'll go pull the carbs off today. It should be quicker the second time, plus I don't have to do any of the additional cleaning / fixing I did the first time around. This is my pep talk to myself Jeremy

I have in fact met your cuz! Well, not personally... I've run across reference on this forum, something to the following effect: "The VMax guys have found that bad or missing rubber jet block plugs causes problems with idling and low speed" This is encouraging to me that this might be my problem. Which is good, because I don't know what else it might be...

Thanks, I am going to try this. But...does anyone understand the consequences of them being loose? I've been searching the web and finding very little about that. The prevailing thought is something that I don't think makes sense. The pilot passage gets fuel from the main jet thru a hole that connects the passages [true]. Without the pilot jet rubber plug sealing, the pilot circuit will pull fuel directly from the bowl [true] and thus the pilot circuit will be rich [i'm not so sure]. I don't think this makes sense because the pilot jet is about a third the size of the main and will be controlling the fuel flow either way. What I think is, since these passages are connected, and especially in the case of the Venture carbs which have two rubber plugs (one in the pilot jet passage and one in the main emulsion tube passage), loose fitting rubber plugs would cause the top-end main-jet metering to be rich because the main circuit can pull fuel past the rubber plugs, bypassing the main jet. Right? Wrong? Weird, because my bike is running well in the mid range to top-end. The problem I am having is that my pilot circuit is lean...needs excessive turns out on the pilot screw (3 to 5 turns) and still doesn't take throttle quite right off idle, as when releasing the clutch. I'm positive everything is clean and installed correctly. I found one reference online to just such a symptom of leaking or missing rubber plugs. Something non-intuitive about the leaking plugs upsetting the balance of pressures in the pilot system which causes the pilot circuit to draw too much from the air-bleed and not enough fuel. I don't understand all the relative pressures enough to get why, but it's consistent with my symptom. Do any of you know? Thanks! Jeremy

As for vacuum leaks, that's a great idea. I did spray the whole area down with the bike idling, first with water, then with carb cleaner. No change in idle, so I don't think there are vacuum leaks. Oh, I also checked the fuel levels in the bowls, which are spot-on. Jeremy

Hey Patch, What is this Black Mr. Gasket sealant? The only one that comes up easily in a search is this: https://www.amazon.com/Mr-Gasket-78080G-RTV-Sealant/dp/B071VZ9CQY This appears to be regular RTV silicone, which is not usually fuel resistant. Is the black stuff made to be immersed in fuel? Also, would you mind clarifying the following? "So in other words soak the rings after reading compression, then you may find that one or two jugs are coming out a touch over max standard, and then you can deal with that after. How I would proceed: Carbs of then compression test, then soak while tending to carbs. " What do you mean by soak the rings? Thanks! Jeremy

Thanks for the response. Yes and no. I didn't use wire. I did clean each jet by spraying carb cleaner thru, blowing compressed air thru, then holding it up to the light so that I could see the hole and ensure that it looked round and clear. This included several angles for the emulsion tubes with the side holes. I've encountered what you describe on bikes that sat with fuel in the carbs. Fortunately that wasn't the case here and everything was pretty clean. Also, it wasn't doing this before, so clogged jets were fairly unlikely. Thx! Jeremy

Hi Folks, My name is Gearhead Jeremy, and I've been an absentee member...I used to frequent this forum a lot. 3.5 years ago I decided that is was time for a change and bought a 2005 Suzi VStrom DL650, really enjoying that. I kept the VR because I just can't let stuff go, and I like it. But my wife's not riding with me any more, and having two bikes just isn't fun to keep up with for me anymore. The other twist is that 3 years ago, before I made this decision, I took my carbs apart (about 120k miles). I've had the bike since 45k miles, and I've never needed to go into the carbs other than the diaphragms. It had a slight stumble under certain circumstances and I thought I'd clean them out and see what I found in there. I got one carb apart, and then they sat on my bench under a rag untouched for 3 years. But that's just silly, and it's time to get this kitten purring again and let someone else enjoy it. I got it back running, but it's not right. I'll list what its symptoms first, then what I did to the carbs. Also, this is related to two other threads in which I asked simple questions about specific aspects: https://www.venturerider.org/forum/showthread.php?141444-87-VR-carbs-rubber-plugs-in-jet-block https://www.venturerider.org/forum/showthread.php?141443-87-VR-Coasting-Enricher-system-is-it-necessary SYMPTOMS - Lean idle and just off-idle 1) Very dependent on choke for good throttle response until it's really good and hot. I'm in Tucson, so I mean HOT! 2) Pilot screws are set at ridiculous settings for best idle - two carbs at 5 turns, and two at 3 turns. Before the rebuild, I had tuned them at some point in the distant past and they were all at or under 2 turns. 3) Even when it's hot and taking throttle, standing start with the clutch still doesn't feel quite right, a little hesitant. Before it's hot, if I try to take off quick with say 1/4 to 1/2 throttle, it drops cylinders / misfires for a second or so. 4) Runs smooth and goes like a bat out of hell once in the mid-range and upper RPMs. Man, this is a nice riding bike. 5) It wasn't acting like this before I took the carbs off. WHAT I DID 1) Replaced worn slides / compromised diaphragms and ovaled-out needle jets / emulsion tubes. I thought for sure that would be the ticket. 2) Found one or two damaged Coasting Enricher diaphragms. Not wanting to spend the bucks for them and thinking their ONLY purpose is to stop the popping on overrun, I plugged the vacuum passages in the caps above these diaphragms to disable the system and stop the vacuum leak. See other thread. I've done this before on a Virago. 3) Carbs overall were quite clean inside. They are cleaner now. 4) Jet Block rubber plugs, two per carb, are pretty hard and don't fit tight in the holes, maybe shrunk. See other thread. I didn't know what they were for and reused them, I am thinking this is likely my problem as maybe it can suck fuel in thru ways it's not supposed to. Not sure how that makes my pilot circuit lean, but sometimes these things are not intuitive. 5) I replaced the bowl o-rings / gaskets, but did not replace the jet block or choke gaskets, or the needle jet o-ring (by the jet block gasket). They seemed OK, and I've had great luck just cleaning old parts in the past. 6) Checked the spark plugs, they look normal. 7) Drained old fuel and put in new. 8) Checked for vacuum leaks by spraying stuff around the boots with engine idling. No leaks. UPDATE TO THINGS DONE 2019-07-29 9) Took it all apart again, found nothing noteworthy. Double-ensured everything was clean, especially the pilot jets and full circuits 10) Rubber jet block plugs were swollen with fuel, probably not leaking. I treated them and the needle jet o-rings with wintergreen oil which made everything supple again - magic. 11) Replaced jet block gaskets 12) Put it all back together. No change to symptoms. 13) Carb#4 fuel level is erratic on the low side when idling. Did I mention it wasn't running like this before I tore the bike down? My garage is fully enclosed and insulated, and my kids are grown, so the bike and parts were undisturbed all that time. I did drain the carbs 3 years ago before abandoning them, which fits into my "shrunken rubber plugs" theory; maybe they need the fuel immersion to keep them swelled up? So - carb geniuses out there - do these symptoms speak to you? Thank you!!!!!!!! Jeremy

Hi Folks, Second in a series of carb questions. The Mikuni carbs each have two rubber plugs in the bottom of the jet block, below fuel level. I've never encountered this before. They are both hard and fit very loosely in the holes (all carbs). What are these for? Are they supposed to seal in the holes and block fuel flow into the jet block via those paths? Will they soften and swell at all when submerged in the bottom of the bowl for a while? If they leak, what would the symptoms be? Mine were out on the bench and dry for 3 years, so I don't know what they were like before I first drained the fuel. I put the carbs back together this way. The bottom of the bowl prevents them from falling out, but they are loose and by no means seal the holes they are in. Maybe sitting dry allowed them to shrink? Full Story: https://www.venturerider.org/forum/showthread.php?141445-87-VR-carb-problem&p=1062867#post1062867 Thanks, Jeremy

Hello! My 87 VR with lots of miles has 1 or 2 damaged coasting enricher diaphragms. Those pups are spendy. I'm under the impression that these valves: 1) Allow part of the air into the pilot circuit and are normally "open" with the spring pressure. 2) They only close under very high engine vacuum, higher than idle vacuum. This happens briefly when the engine is revved and the throttle suddenly chopped closed, or when using lots of engine braking. 3) Under this condition it's common to have a lean misfire, which allows unburned gas to go in the pipes and pop. By closing part of the pilot air, this systems enriches the pilot circuit under this coating condition. 4) It has NO OTHER FUNCTION or impact on the running of the engine, other than the pops in the pipes and associated emissions. 5) A leaking diaphragm would cause two things, first, a small vacuum leak, and second, the enricher might not "enrich" under high vacuum. Is this all correct? IF SO...can they simply be disabled by plugging off the vacuum where it comes into the top side of the diaphragm? This allows the springs to keep the diaphragms down, coasting enrichers OPEN, the full pilot air flowing, stops the vacuum leak, and makes the diaphragm inoperable. More what I'm asking is, are there any other side effects to disabling this system? Full Story: https://www.venturerider.org/forum/showthread.php?141445-87-VR-carb-problem&p=1062867#post1062867 Thanks! Jeremy

Ah. Thanks for the thorough explanation!

Thanks! Block off plates - are those to eliminate the EANDS on the forks? Why do this? Is there a consensus that it doesn't work?

Hey David, I'm not far from you as I sit at work near the Tucson airport and put off working... We sure have had some outstanding weather, but today is a bit...breezy...

Well, I've had this bike since 45,000 miles to its current 115,000 miles, and never replaced the fork bushings OR seals! I'm telling you, fork protectors are the key for the seals. As for the bushings, Earl, have you personally seen a front wobble repaired by replacing them?