My 83 Vision with 23K fried its stator. Let me back up a little. After reading a lot on this site about stator trouble I checked a few things. Measured the side cover temp after a long ride, 230 F. I was worried so I checked all the connectors I could get at. Made sure they were clean and put dielectric grease in them. Went for more rides and decided to see how high a speed I could get on my stock 83 Vision with fairing. Close as I could read the speedo I just made it to 100 mph. On the way home the main fuse burned out. After disconnecting a lot of things the fuse still burned out. Hauled the Vision home in my truck and started taking thing apart. Found burned stator.So I assumed the r/r is toast as well and found a G7 stator and Mosfet r/r. A year later I finally got around to putting things together. Found an extra brow wire on the stock r/r and was not sure what to do with it so went back and checked the original r/r. It checked out in good condition. The fuse still failed even with the r/r disconnected. Removed the whole wire harness and unwrapped all the tape, no short could be seen. Re-wrapped the harness and put it back on, still has a short. Started over at the fuse block and found the first connector on the main power line was internally shorted. It had heated up and melted the the plastic until the plus an minus touched. This blew the fuse and allowed the plastic to cool with the connector still shorted. I broke the plastic away and checked the tightness of each connector when slipping a spade in. Not very tight. I went around the whole harness, removed and tightened every female spade connector. Replaced the melted plastic connector with a good used one. Replaced the starter clutch bolts and lock tight and peened them. Checked the big nut behind the starter clutch, OK. Now I think I have the stator, connectors, and starter clutch fixed. The last thing I did was drill and tap the rotor bolt and installed a .7 pilot jet. I also drilled some drain holes in the side cover around the stator mount so oil would not accumulate. Started the bike and I have 14.5v at idle. Went for a ride and measured the temp on the cover, 190 F. I like the look of a naked bike so I left the fairing off and went or a speed run, 105mph. Then checked the temp again 195 F. I won't claim the lower heat is all due to the oil cooling but it is running cooler and time will tell if the stator will last. Honestly I think the loose fitting connectors are the biggest problem.
Fyi, my '83, with all fairing pieces installed, has red lined the tach in fifth gear many times. The speedo was reading 120 mph. V (actually most bike speedos) speedo's aren't very acurrate. The tach really tells the tale.
Your lowered operating temps are good news. However, there are two varibles that might be at least partially responsible, ambient air temp at time of engine temp reading and change in fairing configuation.
I don't think many would argue excessive temps are the bane of the stator but how to combat the problem continues to be a hit or miss affair. No two Visions are the same as far as fuse type, quality of all connections, stator brand, R/R type, battery type/health, rider style, environmental conditions, accessory load, etc. It's difficult to come up with a fail safe protocol everyone is able and/or willing to follow.
It sounds like you worked through your problem quite satisfactorily and spent some quality time with your V in the process! :D Those are great tips to try for anyone still struggling to keep a stator alive in their Vision. Just to clarify - was the new lowers temps and 14.5 idle voltage using the original or MOSFET R/R? BTW, the brown is a fused source of system voltage sensing for some R/R's. I don't think MOSFET's require that connection.
Also, what type of fuse block was in use when the melt down occurred? Did you happen to photo document your oil cooling and drainage hole mod?
You said you drilled & tapped the rotor bolt, then fitted a .7 jet.
Could you please clarify what you mean by the rotor bolt please.
Thanks
Quote from: cvincer on December 12, 2012, 09:26:11 AM
You said you drilled & tapped the rotor bolt, then fitted a .7 jet.
Could you please clarify what you mean by the rotor bolt please.
I'm also curious about the drain holes under the stator mount... Is this procedure documented elsewhere?
Quote from: cvincer on December 12, 2012, 09:26:11 AM
You said you drilled & tapped the rotor bolt, then fitted a .7 jet.
Could you please clarify what you mean by the rotor bolt please.
Thanks
Rotor="flywheel" He has tapped into the oil running through the crankshaft to direct a metered stream of oil onto the stator in an effort to cool it. This is purportedly used in some Yamaha V4 designs and has been tried by several members. The second part involving draining accumulated heated oil through drilled holes may be a novel idea. Inquiring minds want to know more! :D
The bolt picture is attached. I cross drilled a hole to spread the oil around more. The nice thing about the jet is I can remove the cover plate to change the jet size if needed.
The first temp was checked with the fairing on, and the second temp was checked without the fairing, after I modified the bolt. I did wonder if the fairing affected the temp so after my ride I put the bike on the center stand and ran at 3000 rpm until the cooling fan started. The temp did not change with the fan running. I assume the temp would go up if the coolant temp went up. The oil temp is controlled to some degree by the water cooling.
No picture of the drain holes. If you look at the inside of a cover with the stator removed and imagine where could the oil drain down you can see where holes would help. I drilled 4 holes 1/8 inch in diameter as close to the outside wall as was easy to manage the drill.
My speed was mentioned as a reference for with and without the fairing. I don't think 100 mph is fast for a Vision or any bike for that mater. I know guys racing Ninja 250's at 108 mph, still not fast by any standard but pretty good for a 250 econo sport bike.
This Vision is a work in progress. No particular goal in mind. I just want it to run and will mess with things as I see a reason to do so.
Just for general info about myself I have been roadracing since 1976. My best finish was 10th at an AMA pro 250GP race. I was one of the guys on track that made Rich Oliver look fast.
Sorry I didn't answer about the fuse block. When the connector failed the original fuse block was on the bike. I tried to tighten the clips on the fuses and 3 of them broke. The replacement block I found at a local auto parts store. The one I used has 5 blade fuses and spade connectors exiting out the side. The 5th position is not used except to hold a spare fuse.
Sorry, I am being a bit slow here! Am I right to say the entire length of the flywheel bolt is drilled out and then partially tapped The .7 jet then screws in to below where the cross holes are drilled so that the jet is regulating the flow to the cross holes? Thanks
Pinholenz, you got it correct. I can sometimes be too wordy so I tried to shorten what could be a long, detailed, boring description. I guess long and detailed is what was needed. In the end the bolt head was drilled larger to the point below where the cross hole is, then tapped to the jet thread. Since I wanted the oil to go mostly radially out the cross hole I cleaned the hole and sealed the end hole with blue sealer to just before the jet. The sealer can easily be removed and resealed, if I change the jet. Later year Yamaha Ventures had a wire in the hole to keep it clear. Some owners removed the wire and this caused the oil light to flicker at idle. The Venture also had an oil scraper plate to get the oil off the rotor. I rely on the drain holes and gravity. I could be losing some power from oil drag but not a lot as indicated by the speed run.
To clarify about the r/r. The original r/r was on the bike at the time the stator failed, and because I was uncertain about the function of the brown wire I reinstalled it and checked the charge voltage at idle, 14.5 v . My hope is this is a good sign the r/r was not damaged.
I think I covered all the questions. If more please ask. If I messed up in description, or repairs, or ideas let me know.
Helpful description, thanks.
And I guess the sealed bolt end will also prevent the jet coming loose as well as ensuring the oil gets distributed out the sides of the bolt.
Can you recall what size drill went right through the bolt? Did you do this with a drill head on a lathe? Cheers.
I have a friend with a quality lathe and collets. He did the drill and tapping for me. I have a note somewhere with the sizes of all the holes. Will post when I can find it.
Glen, thanks for the clarification on some well documented mods. :) As far as your V being a work in progress - most start that way and many still are! Making changes and improvements is part of the fun of motorcycling.
Regarding top speeds runs....I have what I think are realistic expectations from a Vision and the speeds you mentioned seem reasonable for a bike of this weight/HP in street trim. I'm also not surprised a fully faired example suffers a bit more from the effects of wind resistance over a naked version.
QuoteMy best finish was 10th at an AMA pro 250GP race. I was one of the guys on track that made Rich Oliver look fast.
I raced only briefly raced in the mid 80's but my feeling is anything better than a DNF is a good day!
When you find them I would really appreciate your main drill size for the bolt,
And, out of curiosity, what sort of charge voltage do people get from a good stator and R/R when the bike is driving and the headlight is on?
It will vary depending on many factors including where it is measured. Mine maintains around 14.3 at the battery and I'm guessing mid 13's at the headlight? Having the original fuse block may lower this number as will poor connections including those of the left handlebar switch and key switch.
The rotor bolt as I had it drilled:
http://web.ncf.ca/ag136/bolt.jpg
Are you both using a Mikuni or a Keihin 0.7 carb jet with a slotted head for this mod ? With all the different conventions for numbering jets etc, I am confused as to what I should be ordering.
From the jpg pic it looks a bit like a Keihin 99101-124 slow speed air jet?
http://www.pjmotorsports.com/keihin-jets.html
I think I will go for style of mod that glenc44 has tried with the cross drilled head.......
I used George,s drawing as a starting point and added the jet for easy changes. This also allows for plugging the whole thing if I desired. The jet is from a box of spare jets my friend has. Don't know if Mikuni or Kehien. I would go down to the nearest motorcyle or scooter store and ask to see their shop assortment. Pick something that has a head no larger in dia then the threads, and a hole around .7 mm. I don't think slightly larger like .8 would make much difference. Then drill the proper holes for threads and counter bore, tap and install. Be creative. Thanks George for the inspiration.
With old OEM stator & R/R.
At idle 14.5v with low beam on 14.7v
" 2000rpm 14.4v " " 14.6v
" 2500rpm 14.45v " " 14.5v
After a ride with ambient air them of 84F
R/R temp 149F
Stator Cover temp 229F (black tape stuck on cover for true reading otherwise heat gun read 195)
Front Cyl Head temp 200F (Heat gun pointed at hex nut adjacent to spark plug)
Rear " " " 200F " " " "
Thanks for the data, Excellent benchmarks.
Thanks CVincer
in proper measurements...
After a ride with ambient air temp of 29C
R/R temp 65C
Stator Cover temp 109C (black tape stuck on cover for true reading otherwise heat gun read 91C)
Front Cyl Head temp 93C (Heat gun pointed at hex nut adjacent to spark plug)
Rear " " " 93C " " " "
That's better, now those are numbers that I understand!
Had a productive hour today at the local bike wrecker scouring through a mountain of brass emulsion tubes and jets to find a jet that would do the bolt mod. Got a couple that look like #70 that should be perfect and 3x #80's unbranded with heads wider than the thread diameter. They would do at a pinch.
I have two questions, probably to glenc44:
1/ Is jet screwed to bolt or is it only interference fit?
2/ Is bolt head drilled from two sides or just one hole?
I borrowed George's picture.
This is my understanding of glens work so if I'm mistaken I'm sure he'll clarify.
1/ Is jet screwed to bolt or is it only interference fit? screwed into cut threads
2/ Is bolt head drilled from two sides or just one hole? one
Additionally, the jet resides below the cross drilled hole shown in red in george's borrowed diagram. The end of the top hole is sealed to force oil to travel through the single cross drilled opening. ;)
OK, thank you.
I have modded Georges diagram again. Thanks George. Hope this helps
I guess it wont make too much difference if you drilled right across the bolt or on just one side, but straight across would keep things balanced.
2 things. 1st...dielectric grease...should not be packed into connectors. Dielectric means "insulator". Thus impeding electron flow. This grease was designed to keep water out of automotive distributor caps and spark plug wires and NOT conduct the high spark plug voltage. Thus, use it sparingly.2nd- The rotor/flywheel bolt drilling does help. Yamaha did this on the Ventures after the 1st year '83 models fried stators in less than 20k miles. There after all Venture 84 on has the drilled bolt and washer design. The washer is oddly shaped to ..I guess help spread the pressurized oil. Note: the washer does not move. Does not move but distributes the oil on the stator.That's why I call it special. I honestly do not know the spec/size of the hole which sprays out the end. Unlike the diagrams I see pictured here, the yamaha design sprays stright out the end. Not radially.No cross drilling. I have 2 Ventures and still cannot figure out that TINY hole's bore size. The oil cooling works...but it does cost some loss of oil pressure. Meaning during summer temps you must run a 15w50, 20w40 or 20w50 oil. My Venture runs 20w50 Mobil 1 90% of the year. GLENN, Lastly, I do not understand exactly where you drilled the 1/8" holes. They just for drainage of oil?
jasonm ........ will the Venture rotor/flywheel bolt fit the Vision? If yes, would be easier to buy than drill.
Curious as to why you are concerned about packing a connector with dielectric grease, looks like it would just offer that much more protection from corrosion and moisture. Current will flow in metal to metal contact and shouldn't decrease until resistance increases or moisture shorts it out. BDC
Quote from: cvincer on January 27, 2013, 07:01:08 PM
jasonm ........ will the Venture rotor/flywheel bolt fit the Vision? If yes, would be easier to buy than drill.
The Venture rotor bolt upgrade included several parts other than the bolt... plate covers to confine the oil, and a "slinger" to distribute it...
http://www.venturers.org/Tech_Library/?action=article&cat_id=001007&id=413
This from the interwebs which everyone knows is infallible. ;D
"Dielectric grease is a silicone-based lubricant that does not conduct electricity. This is a very useful property to both waterproof and prevent corrosion on electrical connections. Because the grease does not conduct electricity, it will not interfere or scavenge power from the electrical current going through the connection. This makes it an ideal coating and protectant for any electrical connection from CPUs to automotive batteries and everything in between."
The same source warns: "Although dielectric grease is advantageous if applied correctly, it can also be disadvantageous if applied incorrectly and may prevent a conductor from working at all. Dielectric grease is non-conductive, so if the user does not properly clean the conductor's contact points after applying dielectric grease, current will not pass through them. Dielectric grease also has the potential to melt silicone rubber after several years so they should not be used with conductors that are encased in this type of material."
Like anything else following directions yields the best results. My only gripe is it seems to dry up in connectors fairly quickly.
Slinger ? actually that wire piece stays in the bolt and supposedly keeps it clean. It cannot be seen from the outside
I know this thread has been idle for a while.
In the case of the Venture kit linked earlier in the thread the metal plates are dams. They would cause some oil to be retained. I assume that pooling a bit of oil was the intent.
Being new to the Vision(s) I have been reading the threads. I haven't read all of them but had an idea similar to glenc44. The bolt drilling is a good concept but to transfer heat from the stator it needs to be continuously bathed all around. The bolt with what amounts to angled nozzles is good if the oil reaches the stator.
I have not disassembled my engine yet so I don't have a reference for the relationship or position of the components inside the cover but am certain that another solution would be to spray oil on the longitudinal center line of the stator. There is a lot of turbulence inside the cases and given the shape of the case interior (I do have a loose spare) an approach like the Venture kit would be an improvement.
I am thinking about getting the oil to the center of the stator and distributed as close as possible so it is not blown around but flows where desired. To do this would require a slightly different approach. The bolt would be drilled banjo style with a passage in the center and two small passages below the bolt head. The washer would be replaced with a cup that acts as the washer and as a slinger. The axial height of the cup would be equal to the distance from the end of the crank to the longitudinal centerline of the stator. This would sling the oil onto the stator all around.
Something like this:
(http://plan9.ootfab.com:90/external/Vision/tn_Slinger.jpg)
I considered the idea of simply drilling the hub of the rotor to do this but a simple bolt-on piece seems like a better idea.
To see if this behaves as I am hoping I am also making a plug for the case that will let me put and endoscope in the case while the engine is running to observe the oil dispersion.
Hi Mike, the stator heat solution seems to be solved by using a series R/R, look at the thread below. SH775 R/R. The series R/R limits the output current from the stator, less current equals less heat. This also leaves the oil system intact.
Copy that.
I'll probably do both.
Your bearings need that oil a lot more than the stator does and if one of them spins it is a lot worse than putting a new stator in. I would do the sh775 r/r which will run cooler and even the engine oil ends up cooler with the stator not putting out all that heat.
Have any values on the pump output volume been taken?
A known history of rod bearing failures leads us to believe the oil pump output is just adequate. There are some engines out there that have been modified but I don't know if the oil pumps have been modified for more longevity.
Thanks sir.
I guess I'll open the cases on my spare engine to have a look.
Do you know if these failure are pressure/volume related? Failure of the nylon drive gear related?
I am building a 164cc stroker engine for a Honda ST-90 and have fitted a pump for the ATC185. More volume and other good things.
Maybe I'll take a look at an oil pump upgrade. Maybe larger pump, different gearing. Maybe even relocation (that is a comparatively large and long oil pick-up). The gen 1 VMax engines have their pump in the sump with a short run to the pick-up. Is there a check valve in the pick-up of the Vision pump? Even the Yamaha service manual has little info on the pump.
Quote from: jefferson on June 29, 2019, 10:40:17 PM
Your bearings need that oil a lot more than the stator does and if one of them spins it is a lot worse than putting a new stator in. I would do the sh775 r/r which will run cooler and even the engine oil ends up cooler with the stator not putting out all that heat.
There are probably performance gains, albeit small, due to the lowered parasitic load on the crankshaft. :D
I believe it was the oil pump rotors from a Honda 750 that was used to upgrade the oil pump. A spacer was needed to take up the gap. I'm pretty sure I have one up there in a box somewhere from the Team Good Times guys in Tx.
Both of my bearing failures were specific to the rear rod bearing and when the engine was getting hot and then when it was hot. Spent some time looking at the oil supply chart, but saw nothing that was obvious as to why it was always the rear rod bearing. Only thing that I can think of is the machining of the oil passages in the crank may have been incomplete and faulty.
Quote from: jefferson on June 30, 2019, 06:37:12 PM
I believe it was the oil pump rotors from a Honda 750 that was used to upgrade the oil pump. A spacer was needed to take up the gap. I'm pretty sure I have one up there in a box somewhere from the Team Good Times guys in Tx.
Both of my bearing failures were specific to the rear rod bearing and when the engine was getting hot and then when it was hot. Spent some time looking at the oil supply chart, but saw nothing that was obvious as to why it was always the rear rod bearing. Only thing that I can think of is the machining of the oil passages in the crank may have been incomplete and faulty.
Thanks. Info helps! :D
It is interesting that the rods are fed by a separate passage through the end of the crank rather than picking up the passages for the main bearings. That would subject them to the condition of the seal on the end of the crank.
But I digress since this is a "stator" thread. :D