Replacing a Yamaha V Star 650 pickup coil and stator:
For a bit of background story on how I ended up here, a new mechanic stripped the oil filter bolt that happens pretty easily on these bikes. Unfortunately, when fixing it he got metal flakes down in the engine!
One day the next week I went out to start it and crankcrankcrankcrankcrank. Oh great now what? It took a good 25 mins to get her started that morning on the way into work and nearly the same on the way home, the next morning she was totally dead and would not start at all. Following the diagnostics here: http://650ccnd.com/coil.htm I found my pickup coil was reading very high and was toast. I was planning on maybe cracking it open that weekend to fix the sticky clutch but now I had no choice but to break open both sides.
Pulling the stator cover.
Japanese engineering likes to use lots of bolts close together at lower torque than other manufacturers. Be sure to remember exactly which bolt went in what hole, as you can see below they are all different lengths.
Also remember how your shifter is set up. I took a picture so I could tell later where the dot on the shaft goes in relation to the bracket. In my case dead center in the gap.
Unfortunately the kickstand has to come off to remove the shifter. There is a nut on the back side of the frame you need to keep from turning, it would be better if you had a helper and another set of hands for this part. I was by myself and had to use another box-end wrench on the back of the frame and a breaker bar/ratchet with a cheater pipe on the front. Yamaha really doesn’t mess around with these bolts, they were a bear to get off. Once the wrench on the back turned enough to press up against the engine or my lift I was able to break the nut free.
With the kickstand out of the way the shifter will just slide off the shaft after you remove the bolt in the previous picture.
As you can see I also upgraded from my poor mans bike stand to one from Harbor Freight for this operation for a bit more stability and lift, I needed one for the BMW restoration anyway.
Follow the wiring back up the frame and cut the zip ties as you go and remove a few bolted on wire clamps. Its a bit of a struggle to get these connectors through the downtube, use one hand to press back the big main wiring harness and press these plastic connectors through one at a time. It takes a bit of patience but you can do it.
In this picture the tube is the swingarm bearing tube. The stator/pickup wires go underneith it with the main wiring harness in the backround right under them also pressed up against the swingarm. There is absolutely no way to force those plastic connectors through. The trick I found out is to wrap the stator wires around the main wiring harness where it is verticle and there is more space, see picture. Once that is done, now the main wiring harness is on top and the stator wires below them with lots of space below. They’ll fall right through after that.
This whole ordeal with the wiring would be a lot simpler if you just cut the connectors off. Only my pickup coil was bad though and I wanted to save the stock stator for a backup replacement.
With the wiring free now you can pull the cover off. Its magnetic so try to pull it off as straight as possible or it will bind on the shifter shaft.
Removing the stator:
Below you can see inside of the stator cover with the dreaded stator and pickup coil screws! These screws are notoriously difficult to remove. Some people have used Vice Grips or bolt out tools and replaced them with regular hex head or allen bolts. Others have tried to remove them using those methods and cracked the covers! Those @#$%& are really in there and the lock tight that Yamaha uses seems to be stronger than the surrounding soft aluminum. Be careful.
One method that has worked successfully for several people has been to heat up the bolts first prior to trying to loosen them.
Trying my best I could not get those bastard screws to budge and I don’t have an acetylene torch. I took the cover to a motorcycle shop here in town and told the mechanic to use a torch first, he says “Oh no, we’ll just use an impact wrench” Almost an hour goes by with banging noises from the back and he comes back out and asks if I have a replacement for both pieces because hes going to have to torch it and the wiring might not survive. Should have listened to me to begin with.
In the end they got them off and didnt want any money for it. I gave the mechanic a $20 for lunch anyway for the help.
In this bottom picture you can also see the pool of oil that would have been between the two stator grommets from my LEAK! Oil should never get into that space, thats one less barrier from it seeping to the outside.
By then daylight was fading and strong winds were picking up, a sure sign of a big rain storm any second. I frantically covered the gaping hole in the side of my engine as best I could with plastic bags taped in place and called it a day. No sooner did I finish when a huge downpour soaked everything.
Just ignore the wooden bit on the engine, thats another project for some cast aluminum covers. I’ll write more on that as I get more progress.
Gasket removal. Getting all of the gasket off of this cover was a royal bitch and took nearly all day. When I did the clutch side I found out the secret, put some of the Permatex gasket remover foam on the gasket right away and scrub it in and let it set for a half hour. Then come back scrape off whats disolved and repeat until clean, only took 3 repeats that way. The first time I used a scraper first and the gasket remover second and it just would not disolve at all. I think because I’d scraped off everything to a smooth surface and the foam wasnt seeping in as good. From now on Gasket foam first! It also reduces the number of small chips that get into everywhere and are hard to clean out.
All cleaned! I had to use nearly a whole box of Q Tips and WD40 to clean all the bits of flaked off gasket and crud and oil out of all of those tight spaces.
Thankfully the engine side was much easier to clean, go slow so you don’t get bits of gasket down in your crankcase where its harder to get out.
TIP: The alignment tubes at the very top and very bottom do come out to give you a flat surface to scrape.
Cleaning inside the crankcase as best I could I noticed some deep scratches and this fairly deep nick out of the magnetic rotor… I think this is the cause of all of my problems. Hard to see in the picture but its fairly deep and had a raised edge that I filed down a bit to get the outside surface flat again. When I had R&S fix the threads they stripped out on the oil cover they got some bits of metal inside the engine and it must have caused this. I think the bits of metal knocking around in there took out the coil, those are some tight clearances it wouldn’t take much.
New high output stator and pickup coil from Electrosport Industries!
UPDATE: I have since learned that there have been quite a few failures of the Electrosport stator in even less miles than the OEM. Time will tell how long mine holds out, its not very settling knowing mine could give up the ghost at any time leaving me dead in the water especially with the kinds of trips we do. I’ve been told that ACCEL and maybe Rick’s Motorsport stators are a better bet. The people who have mentioned using Rick’s have said they use heavy guage wire and they are well made but there are so few of them out there I cant give a recommendation. I am going to buy a spare ACCEL stator to keep on the shelf at home myself, this way if mine does go out I have a spare handy or I can have someone ship it to me overnight if need be.
UPDATE 2: My Electrosport stator did indeed end up failing like others I had heard of and I ended up having to replace it and redo everything from this writeup a second time. Here is the writeup on that and diagnosing the failure.
My original stator screws were reusable, the pickup coil ones were bent beyond belief from being torqued by the impact wrench during removal and needed replacing.
The stator is a press fit into the cover. Screw in all three screws until they touch the stator then screw them each in one turn at a time to pull the stator down evenly so it wont bind, when they really tighten up its in all the way. With the stator seated I unscrewed them all and soaked them in red locktight, you don’t want these things coming apart inside your engine! Judging by how much of a bitch they were to remove I torqued all 6 bolts down as tight as fricken possible so they would not come undone. I dont mean putting a cheater pipe on your ratchet and stripping it, just as tight as I could get by hand, although I did use vice grips on the handle of the JIS screwdriver from the toolkit to get more leverage for the stator screws.
Test fitting the gasket afterwards. Its a good thing I did, because I’d put the pickup coil guide too close to the case and it wouldn’t fit! Trimming a hair off the inside of the gasket made all of the holes line up, I sure as heck wasn’t going to undo that bolt now with it locktighted in and tight wire over the head preventing me getting a wrench on it.
As mentioned before, one of the most annoying oil leaks that has developed on my V Star 650 was from the stator wires. In previous pictures you can see they pass through two rubber gaskets pressed into these ribs below. I wanted to do absolutely everything possible to prevent a leak from reoccuring in this spot again.
First oil leak preventative step, seal everywhere those suckers touch with high temp RTV! Once you start putting down the RTV you need to be prepared to slap everything together quickly so it will cure under pressure.
Next: Seal around every wire one by one. I sealed between both gaskets and the side facing outside the engine and left the internal face clean in case some pieces of this come loose inside the engine years later and plug up an oil passageway or something. With the wires thoroughly coated slide the gromments back and forth half a centemeter to a centemeter to draw some of the RTV down into the holes and create a better seal.
With that press the grommets down and create a good seal against the ribs.
Another leak I’ve had in the past was at the front of this cover where the AIS cannester used to be. To help prevent more leaks from cropping up on this cover I used more RTV, this is blue Permatex Gasket Maker that I’ve used before on my Jeep. Just a little dab will do you, thats the trick to this stuff. All you want to do is help glue the paper gasket to the metal on both sides and help seal any imperfections. Run a very fine bead and smooth it out with your fingers.
More black RTV smeared on the flat side of the stator wire grommets. This part only seals against the flat paper gasket (see picture above with the gasket fitted). In my opinion thats the fatal flaw in this design, its just a flat surface here the rubber is pressed against and that may be how these leaks from this spot develop.
UPDATE: I’ve since had a failure of the Electrosport stator and have had to redo all of this work. I can confirm that when the stator wires going through these grommets are each sealed this way with RTV that there is no chance of it leaking. You can see in this picture of my teardown a year later that there is not a drop of oil between the two.
Repeat the gasket maker on the engine side and slap the cover back on it and bolt it down.
All finished! and so far no leaks (knock on wood). All these bolts on the outside of the cover are very low torque, the manual says something like 5 foot pounds. Using one of the short alan wrenches just snug them up a little past tight the same as you would for changing the oil or as tight as they were when you took them off.
Thats it, just rerun the wires, clip them in and reassemble the rest of the bike. Let it set for a day for the RTV to fully cure and put some oil in it and go for a ride.