Blackmax88

Some comments and opinions which may be of help. I haven't seen a manual which says to use the center of the covers as a benchmark but it is used. The "correct" benchmarks are : on the carb body behind the diaphragm cover on the LHS in amongst the "Mikuni", "Made in Japan" raised lettering is a small horizontal bar. This is the mark usually used for fuel measurement with the carbs on the bike. Yamaha recommends you use their graded site glass on plastic tube. There is another similar bar marker on the back of the float chamber but you can't see this with carbs intact. If you want to use the center of cover (and I use it) you must first very accurately locate the center. This can be done by string lining the 4 bolts diagonally top and bottom and marking where the 4 strings (cotton threads) cross in the center. Mark this posi with a fine center punch mark. Get a "Post it" sticker and mark on it "0" then 14mm down from the zero line, and 16 mm from zero. Place the sticker with the zero on the pin mark. Zero is your bench mark, fuel level between the 14 and 18 mm marks. Problem with this is that the cover's bolt holes are usually a sloppy it ion the bolts so the cover is never accurately centered and moves each time you loosen the bolts. All the marks relate to the center of the needle jet, fuel level is +/- 15mm below this. Check to see if the fuel level is holding with the fuel pump on. Float valves with poor seats are known to unseat with vibration or excess fuel pressure. If the rich running is prevalent at mid throttle settings, look for worn slide needles and /or worn oval needle jets. Make sure the air filter is clean. The fact that the previous owner had the idle adjustments screwed in indicates he may have been trying to correct the rich mixture ...it won't. You can see if the idle jets are clear but you can't see if the idle circuits connecting PAJ 1 and PAJ 2 are clear. At the very least you should blow out these 2 jets using a can of carb cleaner with a straw with the idle screws ( and O rings and washers) out of the carb body before attempting to set the idle mixture. Better still if you "shotgun" the carbs, however, setting the idle will not fix the obviously rich setting. If you are absolutely certain that the fuel levels are behaving themselves under pump pressure and are correctly set, the problem may lie with the rubber plugs which seal the bottom of the main jet block. If they are loose (or missing) fuel may be drawn in quantity directly into the throat at all engine speeds.. In the end, you may have to pull the carbs and clean and set them on the bench. FWIW

Couldn't stand looking through a windshield except for low speed maneuvers. My winter shield is set 1" below my eye line so I see way ahead over the top and the weather goes over the top of my helmet, can ride at highway speed in bad weather without helmet visor down or just RayBans. Dark smoke summer shield is 2" shorter again. The lower shield height also prevents eddy currents with rain being dragged behind the shield. FWIW

Which benchmark did you use to measure the levels against ? How many mm from the benchmark was the fuel in the tube ? Was the fuel pump switched on each time you checked the levels ? " " What did you do after you removed the idle adjustment needles ? Have you ever "shotgunned" the carbs ? Have you run up the engine and turned off the fuel pump to see how the engine responds as the fuel level drops in the carbs ?" "

Opinion: The symptoms indicate that the fuel levels are much too high. How are you measuring the level ( in the tube against what benchmark) and how many mm are you reading ? What did you do after you removed the idle adjustment needles ? Have you ever "shotgunned" the carbs ? Have you run up the engine and turned off the fuel pump to see how the engine responds as the fuel level drops in the carbs ? If the carbs are correctly syncronised,the fuel levels are within spec AND the idle circuits are clear and operating normally then adjustments to the idle screws will have noticeable effect. 2 1/2 turns out is a only starting point for tuning the idle range in these Mikuni downdraft carbs. The final settings could be a turn or more either way. FWIW All this assumes that the engine valve clearances are within spec

OK, I see it's a '96. The EBC dealer wanted to know.

I've thrown the question of the EBC spring at a supplier, so see what turns up. Previously we (Vmaxers) have doubled up on the diaphragm spring known as a 'double D' improvement. It makes the pull on the lever a bit harder which of course you notice around town but cures any clutch slip. Don't know if you could do it with the Virago, should be possible, just involves fitting 2 springs. But you have a cable operated clutch so that may put some unacceptable strain on the cable. Umm, have to think about that. BTW, what year is the Virago ?

You could be right about the EBC spring for the XV1100 (1TA 16334-00-00). Don't know if the spring used in the VMX1200 and Gen I Ventures will fit ( 1FK 16334-00-00 ) you could check with "Parts Giant". Yep, at 100k/kms the clutch should still be OK with normal use. We've had a couple of RSV and a Vmax in with clutch slip. In all cases the plates measured up within spec and the friction inserts did not appear hardened or burned. With the Vmax, the spring was replaced with an EBC after market although the OEM spring was within spec). Both the RSVs had the clutch plates cleaned up and deglazed as mentioned previously, and sent back out. That was several months ago and haven't been reported slipping since. Both RSVs had been on semi synthetic 10/40.

By-passing a non functioning fuel pump will work providing you have sufficient head of fuel in the tank. The problem is that the seat diameter in the Mikuni carb float valves is smaller in engines with a (low) pressurized fuel system. The float valve seats used with gravity fed carbs have a larger diameter and capacity to flow fuel. One risk with by-passing the pump is that if your right hand makes the engine use more fuel than the (normally pressurized) float valve can pass (under gravity), you run the risk of leaning out the mixture with consequential piston damage. FWIW

You don't say how many Kms on the bike or what oil you are using. If you're on synthetic you can expect slippage if the diaphragm spring is a bit weak after ??kms of service. You should think about pulling the clutch plates out, wash them down in degreaser and clean up. You may find that the friction plates are within spec, not unusual. Wash everything in hot soapy water and let dry.. Get 400 grade wet / dry then deglaze the steel plates. Fit a new EBC diaphragm spring ( $ 45 and 10% stronger than stock), soak the friction plates in API SE,SF,SG mineral oil, change the engine oil to the same API grade, install the clutch and ride for another 200 000 kms. Forget the Barnett conversion and full synthetic oil. IMO. FWIW

Mecasonic was looking for suggestions on how to improve the braking on his '83 Venture, my small contribution attempted to address, that tho I'm sure it's been done to death elsewhere. As with all forums you get out of them what you can. "Small point: his is an 83 which would be internally vented discs, 86+ was the solid discs with slots" I referred to these early discs as "solid" as opposed to later "floating" discs. The ventilated 282mm dia are in fact a composite disc with the brake wearing surface fused onto the steel carrier. Some may know that, because of the jointing of the wear surfaces, that these discs should only be mounted in the correct rotation direction. There is a (small) direction arrow on the outer face of the carrier showing correct rotation. A close look at the brake wearing surface will show there are 3 segments to each side with the splices in one direction. Tho replaced by more effective calipers and larger disc on the front end,these early discs continued to be fitted the rear end to many other Yamaha models. IMO, the best bank for his buck, to upgrade his '83 brakes is to fit RI calipers ( alum or steel pistons OK), to his '83's forks with adapters ( 2 pot Sumitomo caliper bolts 83 mm c/c with Yam 4 pot caliper's bolts 100mm c/c) . This mod will necessitate fitting 298 mm floating discs. Re the m/c. Blue spot 4 pot RI calipers are a popular upgrade for the RSV as well as other bikes but much "feel" is lost at the brake lever if the original (large bore) m/c is not replaced. Sure the bike will stop but with more hand pressure and less sensitivity / feel at the lever. Probably worth a mention is the type of brake pads employed, particularly with stainless steel rotors. FWIW

Your bike has Sumitomo 2 pot calipers and 'solid' 282 mm discs. If you want to upgrade to 4 pot calipers you have the option of changing the fork lower legs to the later model as suggested or finding a pair of adapters which will allow you to hang the 4 pots (RI/R6) calipers onto the fork's existing caliper lugs. You will then need to fit 298mm semi floating discs. The early model RI calipers function best with a master cylinder with a piston dia of 14mm.( Vmax or FJR will perch on 7/8" handlebars) This conversion is popular with owners of earlier Vmaxes ( pre '93 with 40 mm diameter fork tubes) as upgrading the pre '93 models to 4 pots and 298mm discs without adapters involves the change over of the complete front end ( bigger calipers and discs were fitted to the later Gen I Vmax with 43mm diameter fork tubes). Caliper adapter / hangers are difficult to find but they are out there. Braided lines are a priority, plenty of off the shelf lines or custom made. FWIW

Have to agree with all that's been said so far. I have a fixed backrest on my '06 RSV and would not ride without it these days. Don't know wot breed it is, bought new off e-bay and set up by me for my 6' 2" height. The rest itself has a bit of "spring" in it which gives a little when you push back. The support it gives my lower back is excellent. Only negatives are that you cant 'throw your leg over" the saddle you have to step across the bike and same thing goes for passenger getting on/off. Possible a fold down would work better for some. It doesn't detract from the bike's appearance.

The K1350YK you mention was the kit I intended to suggest but it got 'lost' somehow. You will notice that the float valve seat does not have a filter/screen ? The float valves/needles sold by Georgefix have the screen. Don't forget the anti seize (moly grease) on the idle adjuster threads. FWIW

Also didn't notice anything about upgrading for the 2nd gear issue, never owned one but heard they had the similar shim wear problem as our early 1st Gens They did and the second gear problem was amplified by the fact that the Vmax applied nearly double the Venture's HP thru the transmission. The 'Max and the Gen I Venture share the same basic engine but even after the second gear problem was fixed by Yamaha, the Vmax could still slip second gear, often, due to riders "race changing" from 1st to 2nd.Once the dogs start to disengage, they only get worse. Usual fix is to get the gear's dogs undercut.

"So, I wonder if it might have the updated design? Guess I'll have to take a look" Not difficult if you have the time but before you do you may want to think about fitting an oil pressure gauge first. Mechanical or electronic it's not difficult, I prefer to make up the fitting rather than buy an expensive kit and have set up gauges on all my 'Maxes since 4 out of the 5 engines I've worked on had blown O rings, all identical faults. If you go the gauge route you may not have to drop the pan and even if you do take a look, the gauge is a good addition. On the problem itself, the O ring is not the problem....the design of the elbow, the oil pan support and the port which the elbow fits into ( 4 poorly designed details) all contribute to the problem. This combined with an oil pump pressure relief setting way above what's necessary all contribute to the O ring blow out. If Yam had redesigned one of these defects it may have solved the problem. There are several ways to "fix" the problem, the bracket shown in the article is cheap and it works but not what I do. Agreed about the braided lines. There are many more upgrades which the Vmax benefits from. FWIW

Hats off to that guy. Having done three Vmax rebuilds myself and ownd Vmaxes for 25 years he's covered the job warts an'all including his own mistakes. The pics are a great help to anyone wanting to rebuild a Max or a GenI Venture. Without "nitpicking" I'd draw attention to the infamous "Orange O ring" problem in the oil pressure gallery. Stated that this feeds the top end of the engine....it does supply oil to the camshafts but it mainly supplies oil to the crank and all main and big end bearings. This O ring displacement is common in all Yamaha V4 engines until Yamaha 'quietly' changed the design of the pressure elbow and O ring (without telling anyone) around 1998 so any V4 made before that date will have this problem. It just doesn't show up on Ventures because the engine is less stressed than the Vmax engine. An engine with a blown O ring will have zero zero oil pressure at hot idle and around half normal pressure above idle. If you ride in the high temperature / high rev zone with a blown O ring you are courting crankshaft disaster. Fortunately for Ventures, they don't get into this zone. The Vmax does. FWIW.

http://www.ebay.com.au/itm/86-93-YAMAHA-XVZ1300D-VENTURE-ROYAL-NEW-K-L-CARBURETOR-REBUILD-KIT-18-2879-/400628530806?hash=item5d47523e76

The idle jets themselves do not get blocked but the fine bore circuits connecting them do, particularly the system connected to the idle jet/idle screw. You wont clear them poking around with wire. The idle circuits influence engine performance from idle to around 3000 rpm under light loads. You have a good chance of clearing the circuits without removing the carbs if you "shotgun" them, a common method used by Vmax owners. I always shotgun mine before a carb sync, keeps the 'Max running sweet. Google "Vmax shotgun carbs" for several methods, tho most of us have our own particular method. It will take you about 2 hours first time, then less than an hour next time. You don't need compressed air. FWIW

You should contact Sean Morley of Morley Muscle ( one 2 demax). Sean is a dedicated Vmax and Venture repair and engine modifier, stocks parts as well as rebuilt engines. He's quite approachable, happy to advise and knows his stuff. Google his details and contacts. There's not much he doesn't know about both bikes. PCW Racing modify the Gen I Vmax engine to 1500 cc, called the 'Tourmaster". This brute will put out around 160 RWHP with some add ons.

If you want to identify exactly where engine noises are coming from and what they might be, use a long screwdriver (preferably metal thru the handle or plastic) or a socket breaker bar as a 'stethoscope". Place your thumb over one end and stick it in your ear. With the engine running stick the other end on the suspected noise location. With practice you will identify bearing rumble, pin slap, valves and other mysterious sounds. Remove thumb from ear when finished.

The symptoms you have.....wont idle without choke but runs OK at higher revs are typical of blocked idle circuits in the carbs. Can be caused by a build up of fuel gum from standing, dirt or rust dust passing the fuel filter and can strike at any time. I'm a long time Vmax and Venture owner so have some experience with this common Mikuni carb problem. Unless the idle circuits are blocked by corrosion ( unusual), a simple "shotgun" will usually clean out the carbs without taking them off the bike. Take you a couple of hours if you haven't done it before and cost you a few dollars. The Mikuni downdraft carbs on GenI and Gen I/ 2 Ventures are similar to the Gen I Vmax carbs so same technique applies. There are a few tips available which may help if you decide to go ahead, just holler. FWIW You'll find info on Google....dial up " Vmax shotgun carbs"

The 'oil warning' light is actually an oil level indicator not an oil pressure indicator. If the oil level is low, under acceleration or on a positive incline, the warning light can come on simply because the oil level sensor is at the front end of the oil sump (the pump is toward the rear so will not be starved of oil ) . This is a common condition with the Gen I Venture and Vmax engines. Just top up the oil level to mid way on the sight glass with the bike standing level.

YOU MEAN THERE ARE FOUR CYLINDERS ON THE RSV? Yep, include the 2 master cylinders, that's 4.

FWIW, after 20 years, 1985 - 2004, run the Gen I Vmax was mooted to be replaced and talk filtered to the Paris Motor show of that year. Production of Gen I stopped in 2007, 3 years after the talk started. The Gen II Vmax was released in 2009, 5 years from gossip to go. If Yam follow the same pattern, hoo nose, there is a while to go.