nortap2 Posted May 28, 2017 Share #1 Posted May 28, 2017 Hello everyone first off i would like to start by saying sorry for the bad punctuation and spelling ahead of time. I recently got a heck of a deal on a 1985 venture royal with only 27000 miles on it from the second owner. It cosmetically is in great shape and could tell that it had been garage kept only downfall to the bike in general is that he let it sit for a year and the carbs needed cleaning, so having a pretty decent back ground with passenger vehicles i decided to purchase and tackle the carbs myself. I thought how hard could it be. Well 2 weeks later i got the bike all back together and running pretty good (now that i have read thru some post on this site I have realized that I have cut a lot of corners). Well being the wheeler and dealer that I am as I was scrolling thru craigslist i stumbled upon another venture royal same year same color but did not run but had a few extras that my bike did not have like aftermarket tailpipes,highway pegs and a crystal clear windshield,but did not run and was missing rear wheel and tire. So i figured for 100.00 it was well worth it and bought it with intentions of taking off the extras and putting them on mine and stripping the rest out and saving just encase. Well i put the exhaust and took it for a ride the other night and once it warmed up it idled really high. i have tried to twist idle screw back to bring it down but it still is not right. I would really appreciate any feed back and i thank you ahead of time for your patience i am new to this and still trying to learn. Oh and by the way i after i cleaned the carbs i did not sink them I am currently in the process of making my own. Sorry for the background story. Link to comment Share on other sites More sharing options...
rbig1 Posted May 28, 2017 Share #2 Posted May 28, 2017 well have a question when you play with throttle. does it have freeplay at idle position. you may have to adj cable joint. make shure the throttle is moving through the range by watching the carbs. and your carbs could be way out of sinc. one cylinder doing to much work. some of the pros will chime in here. welcome Link to comment Share on other sites More sharing options...
snyper316 Posted May 28, 2017 Share #3 Posted May 28, 2017 Yeah it sounds possible that something isnt seated correctly, You could have number 2 carb shut and the other 3 open some what enuff to make it race. You could be bound up somewhere in your cables. Which if you try to twist your throttle you should feel some play there. Ummm you got a heck of deal on parts bike. Sorry had to throw that in there, it can be a number of things I would first start with making sure everything is seated properly. Good luck with making your own sync, but that is another good thing to check but I have had mine way out but never had the engine racing. I did one time when my push cable was wedging the throttle open. It was broke, over Christmas I finally got a cable and replaced everything. Um the only other thing is maybe cruise is somehow not letting it to close all the way? Have fun with the bike and Welcome. Link to comment Share on other sites More sharing options...
bongobobny Posted May 28, 2017 Share #4 Posted May 28, 2017 MY question would be, are you sure you adjusted the IDLE screw and not one of the carb sync screws?? The idle adjuster has a knurled wheel on it and is sort of hidden. The carb sync screws are screwdriver adjustments. A bad vacuum hose can cause the issue you described so check your lines, and make sure your caps for carb synchronization are not leaking or missing either. And while we are on the subject, did you properly sync the carbs after you had them off and apart?? You done good on finding the other bike for $100 especially seeing as selling them in parts on ebay can net you over a thousand dollars!! The upper fairings, if in decent shape, can bring at least $100 each!!! There is an excellent DVD you can buy by a guy named Damon Ferraro (sp) that goes into very extensive detail concerning rebuilding the carbs. It is a VMax video but is appropriate to the Venture carbs as well. it costs $12, or you can also buy his video on rebuilding the engine as well for a combined price of $22, either video is well worth the money! There is also a downloadable Factory Service Manual available here on the site which will also provide you with some valuable troubleshooting information. Look in the 1st Generation Technical Library in the Read Only section. Welcome aboard!!! Link to comment Share on other sites More sharing options...
syscrusher Posted May 28, 2017 Share #5 Posted May 28, 2017 To me, your fast running sounds a lot like my own 1993 back when I initially got it. The solution for mine was to replace the carbuerator diaphragms. These carbs are a constant velocity (CV) design that needs a sealed system amongst the four carbs. If sealed the engine vacuum will control the throttle air flow somwhat evenly distributed between the four. If diaphragms have tiny holes it's unpredictable mostly, but mine ran fast and couldn't be adjusted down. Super glue can seal some of the holes temporarily for testing. Let it set up properly. If this seems to put you on the right track, buy new diapragms. There once was a source listed at the top of the forum, but you can search on "diaphragm". Link to comment Share on other sites More sharing options...
CaseyJ955 Posted May 28, 2017 Share #6 Posted May 28, 2017 It's going to be difficult to diagnose running problems without a good synch. If you had the carbs apart already and when reinstalling them make sure they are completely seated into the intake boots, check for any other vacuum leaks. With the carbs off the bike and the rack separated they are almost certainly out of synch and that can account for erratic/high/hanging idle, lack of responsiveness, chuffing/popping and all sorts of stuff. I was going to do a homemade synch gauge, and I know some guys do pull that off well. I picked up a Morgan Carbtune and it's probably the best $100 I have spent on bike tools. Unfortunately these carbs are not really a set it and forget it. I synch as a part of routine maintenance on both my Vmax and Venture. I toss the synch gauge on at least a couple times a season to keep it sharp and happy. Find a way to synch the carbs and see where that lands you. When you pulled the carbs did you alter the float levels? Also make sure it's hitting on all 4 cyl. Not uncommon for the old coils and HT leads to fail where the HT leads go into the coils or at the caps. I like the downpipe spit sizzle test just for being quick, effective and easy way to make sure you have fire on all 4 pots. These V4s run surprisingly well with a dead cyl. Oh yea, welcome! Link to comment Share on other sites More sharing options...
syscrusher Posted May 30, 2017 Share #7 Posted May 30, 2017 So I'm seeing a lot of advice about synching the carbs here, but what you're doing when you do a carb synch is balancing the vacuum level of the four carbs. If there are holes in the diaphragms it will interfere with the vacuum at the carbs that have the holes, and to a lesser degree the other carbs. Besides that, doing a carb synch requires equipment that costs about $100 while checking the carb diaphragms for pinholes and temporarily sealing them for testing purposes requires time and super glue. There is one final thing required to check the diaphragms that can be purchased at any ACE hardware type store and that is a T25 Torx bit that has a very small recess drilled into the end to allow for that one screw with a pin in the center of it's recess. At ACE you'll be looking for a "Security Bit" set with a full array of the Torx bits in it, you know, cause I could be wrong about the T25 and it could end up being T20 or T30. So when you get the diaphragm out check it in the light and if it has little pinholes then put a little dab of Super Glue on each and let it set for a bit. These won't be exposed to actual gasoline or anything like that so don't worry about the Super Glue, although I don't think gas is a solvent for it anyway. I'm not saying that a carb synch wouldn't be a good thing, but I don't think you can synch it if those diaphragms are religious. Doing this on my 93 got the idle under control and led me down the path of finding the next thing I needed to fix on mine. When I finally did have a carb synch tool to goof with it was anti-climactic, it didn't make a huge difference in things in my recall of it all. I have made a lot more changes since I synched it though now and I probably should check it again. Maybe next weekend. Good luck to you on that uncontrollable idle. Link to comment Share on other sites More sharing options...
Marcarl Posted May 30, 2017 Share #8 Posted May 30, 2017 All good info so far. One item to add to all that: where the throttle cable come down into the carb area, it runs past a shaft with a nylon spacer on it that looks like it might be a slide for the cable. It is not! It is a spacer only. The cable runs behind that shaft. If you have the cable running over that shaft, you won't get much in the way of adjustment in the carbs. Link to comment Share on other sites More sharing options...
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