XJ750 Starter Clutch Replacement...

I recently aquired a XJ750...I'm trying to replace the starter Clutch, and I'm curious if anyone has a link or some info, on the the proper way to replace the springs, and if there are upgrade springs....I've searched all over and haven't found any good info...Thanks in Advance...

 

Can't say I've heard of upgrades for this unit but the springs and rollers are available from Parts and More, one of the new parts under our links column. Pulling the motor and splitting the case are required. You sure the clutch is the issue? Could you describe the symptoms for us, cause the clutch rarely gives trouble to my knowledge. Regards and welcome aboard!

 

I ordered the springs from one of the local Yamaha dealers today....When you hit the starter, you can hear the starter spin but, its not turning the engine over, and sometimes while its "free-spinning" it sounds like something is trying to "catch", and it might even "catch" but it only manages to turn the engine maybe 1/4 of a revolution, then continues to "free-spin"....

I really don't know much about bikes, so I also ordered a Haynes service manual...

I'm actually attempting to replace the springs w/o splitting the case, I got them all out, and I think I can reassemble it if I'm careful....We'll see....Let me know what you think....

 

Well, you didn't mention if you checked out the internals on the starter motor but that could be your issue. Have you jumped the starter with it off the bike? If so, did it spin? There are three planetary gears inside that unit and it could be that they died. I'm going to assume you did that right off the bat. As far as the springs are concerned, use grease to install them, they won't fall out that way. Use it on the rollers too. Use a moly and graphite type assembly lube that is soluble in oil, like Sta Lube, it will not cause issues with your oil but you may wish to change it shortly after this evolution. Another issue is the starter chain itself. If your issue is worst case, the chain is skipping over the teeth of either the crank or the cluch. I very seriously doubt this. First the starter and then the clutch. Were the springs you pulled out deformed in any way? Were they in pieces? If so, you found your problem. No pressure against the rollers and the sprag will never lock up. Had a buddies GPZ do the same thing, three government issue ball point ink pens and a tube of Permatex set it right. Just clipped the ball point pen springs to length. Never heard from him again about that issue ('88). Guess I ought to give you a chance to respond.

 

Let me first say that I'm a ASE Master-Master Auto/Truck Mechanic, so wrenching isn't new to me... I got the bike for $140...I figured it would be fun to learn about motorcycles...No battery, the guy didn't know if it even ran....I got it home and hooked it up using a 40/200A Battery Charger...Nothing-No click, no spin....I took the starter off and cleaned the brushes, and armature contact points....Now the starter works well ( I also ordered new brushes to remedy future issues).....I put it on the bike hoping it would fire right off....It did what I described in the earlier post, so I searched the mighty internet and found out info on something called a "Starter Clutch"....Long disassembly story later, I find three deformed (one broke in half) sprag roller springs.....Parts should be here late next week, and I'm hoping for the best.....I'm sure I'll have some other issues, but I like to learn how to ride, and use it to drive to/from work....There's no traffic, and its never really busy during my commute.....So there's my story.

My question is, is it possible to replace just the springs w/o taking the motor out/splitting the case open?? I took out the charging mechanism, and went through an access plate behind it (3 small torx screws)....I think I'm on the right track, just curious if I was doing it correctly....

 

You would be breaking new ground and I would love to hear of your success. Sounds like your aiming in the right direction. Take pictures if you can or write out the procedure for the forum at least. I had mine out last summer and I remember everything being tucked underneath a flat plate. I am assuming if you got the old ones out, putting new ones back in the same route should be a forgone conclusion. Did you fish the broken springs out of the access behind the alternator? If you did, your my hero! I would not have thought of that. I'm too much of a "in the box" type of thinker. Hard to come up with my own ideas. I've not heard of anyone else doing what your doing. Anyone care to comment?

 

I had mine out of the motor in my hand but I can't remember how much room you would have to try and do this repair while it's still in the bike. I'm sure it's not a whole lot of room. Hopefully one of the springs won't go spronging off on you while your trying to reassemble. Just like Robert, I'm very curious if you can pull off the repair while it's still inside the motor!

 

Well I'm here to say, that I successfully replaced my Starter Clutch Springs w/out removing the engine...It was done completely through the access plate behind the generator mechanism....

A little patience and some long screwdrivers......I think I'm someone's hero now....

 

WOW!
way to go bike-man-man

 

Wahoo!! You indeed are a hero today Bike! Did you by chance photograph any of the evolution? I hope so. If you did, please post! Congratulations to you sir!!

 

XJ900 Starter Clutch

Hi folks. I've got an XJ900 (1985 Australian/European version at 891cc) which I've had for a few years. I've done a bit of work on it and would like to post a pic. soon.

However, the starter clutch might need some work done on it soon and I've heard mixed reports about how it may be accessible without having to split the crankcase; i.e. through the alternator housing.

Can anyone elighten me on this. I've checked the Haynes manual and I just can't see how, even if you remove the alternator innards as well as the bearing housing, there would be enough room to remove something with the diameter of the large end of the starter clutch.

Opinions/assistance anyone please.

Many thanks.

 

Re: XJ900 Starter Clutch

Hey redcentre003 welcome.
Here's another post on the same subject.
Bike-Man-Man says he did it.
At least he changed the springs and rollers.
He clams it can be done, maybe you could PM him and he can give you some more info on the subject.
Good luck, and be sure to post some pics.
http://xjbikes.com/forums/index.php?threads/480

 

Yes, it is possible, however if you drop the rollers, springs, or spring caps in the crankcase, you going to have to do it the "right" way anyway...Be prepared....The keys are some patience and go slow...

I'm doing this from memory so if I left something out or you have a question, please let me know....

First I took off the starter assembly off and the alternator cover and positioned it aside...Next you must remove the stator (the big copper thing inside the cover that spins w/the engine) there's a bolt in the middle to remove, but the stator has to be pressed off the shaft, you'll have to have a special tool...I've seen them on ebay, but I modified an old harmonic balancer removal tool (the threads were the same)...If you look at the stator it has threads cast into its housing, thread the special puller bolt into that, and while turning the puller, the stator will slide off the shaft....Next, remove the three torx screws that hold the retainer plate to the case....Then, the oil spray tube can be removed...Now the tricky part, pull the shaft out of the case (the starter clutch unit will fall down) using long screw drivers separate the two halfs of the clutch mechanism....The half closest to you will have the chain wrapped around it, and half farthest from you will contain the rollers, springs, and spring caps....Using the long screwdriver, hold the farther section up higher than closer, using another screwdriver you can manipulate, and rotate the clutch/roller mechanism around to remove the three rollers, springs, and caps....A telescoping magnet will help alot...Reassemble the opposite of removal, go slow, make sure both halves of the clutch mate together properly, use a dab of grease to hold the springs, and caps together....

I will also add as a side note, as it may or may not be required to do so, but I did have the trans clutch removed while doing this, and I also unbolted the idler gear that goes between the starter and the starter clutch(this is done from the trans clutch side)....The idler gear will fall down an inch but can easily be manipulated with magnets and screwdrivers...

I think that's it....I will say, that not doing this the "right" way saved a TON of time, but it is risky, and could cause engine damage if not done correctly...I had nothing to lose, the springs cost $2 a piece, and I got the bike for $100....It now starts and runs good, although I haven't gotten to ride it yet..

If there's enough interest in this procedure, I'd be willing to do it again, and photo document everything....I will accept donations...

 

Thanks for the detailed account. It will be very helpful. I knew it would be a minefield if something dislodged and fell into the crankcase but I'm prepared to have a go rather than take the engine out and do open heart surgery when the time comes in the next few months.

One question - when you say you split the starter clutch into two parts...from the Haynes manual it looks like the large cog and internal roller bearing/spacer do come away easily but the part that houses the springs etc. are pretty much a single unit right back to the Hy-Vo chain cog. If that's the case how did you ensure that the large cog and internals did not slip away into the darkness of the crankcase seeing that it sits at the end farthest away from the opening - is that where the screwdrivers etc. came into play.

I guess from your account it is the actual clutch body which is turned around inside the hole and the rest of the operation is done carefully through the opening; i.e. that it is not possible to actually remove the clutch mechanism from the bike.

I may have a couple of more questions but this has helped a lot already.

 

Hi's , just done all this
The special tool is just a big bolt , as you see in the pics a thinner bolt goes through the theaded large hole to bolt the rotor on , so a well greased [to remove friction] bolt the size to suit and turn in until the rotor pops off , if its tight a rachett gun is best as one can strain the primary chain or turn it tight and hit with hammer.

 

Whoooa , hit the end of the bolt with the hammer Not THE ROTOR!!!!

Funny when typing this stuff it looks ok then a reread and someone or the way its worded do not come out right....

 

Bike-Man-Man

Clarification please, are you saying that you rotate the clutch so the face that was away from you gets flipped to be facing out towards the generator access hole so you can get to the springs & dogs?

Thanks!

 

edited to correct my own stupidity.

 

I am very impressed and would love to see pictures.

When I had a crankcase split I went through the motions of doing the job you just did, but while having more access to see if it was possible. The issues I found was that the bolts on the starter clutch were on the back and not accessible. Did you turn the assembly around?

When I had the assemble out, I worked on fabricating some tools to use through the shaft hole and found all the tools that I could make that would fit through the hole would not have enough of a sharp bend to be able to seat the springs in the available space.

 

Unlikely you'll see pictures he hasn't been around these parts for over 6 years.

 

damn you, I replied to an April fool bumped post.

 

so this sticking a bolt in there and tightening it down is a load of b.s.!!! Just like i have come to expect from forums, just people telling you to buy assorted manuals and useless info that is pure crap.

 

that's really all there is to it, wait till you get to the peened torx screws

 

what the heck are those

 

if this is a shaft drive, there's a set of bevel gears that drive the u-joint,
under the first one there's 4 torx screws that are peened or staked so they don't come loose. you have to drill the dent out and use a impact driver loosen them.
don't loose the shims when you take the u-joint shaft out

 

Hi Stevo, the way the puller works is like this... the bolt has a long shaft that is not threaded all the way to the end, when you screw it in, the end of the bolt bottoms out inside the rotor shaft bolt hole, and as you apply more torque, the threads that screw into the rotor then force the rotor off the rotor shaft. And while our esteemed colleague Polock is correct in what he's written, it bares no relevance to this thread, for while the rotor shaft retainer plate is secured with TORX fasteners, they are not staked. TORX, for those who don't know is a special fastener that looks like a six pointed star and it needs a special TORX driver.

 

Actually it does in a way, since those replacing their starter clutch WILL eventually be pulling the engine to split the cases to facilitate replacement in the only REAL way it can be done (Wizard's "bashing the roof in" method aside, not many people will want to split their cases quite so literally!), hence they will be likely making the most of the time to fully rebuild the motor as it's apart...

 

Never mind then

 

i don't make this stuff up

 

I don't recall anybody suggesting that you did? :?

 

OK lets clarify one thing right now. My cases have been split(by me) now for nearly a month and i only had to remove two of those torx spits. And i didnt drill nothing out while doing so. Second nobody said thatthere was a an extra tool that went over the starter cluttch removal tool to keep the shaft from balloning out. So luckily after trying just a bolt and impact with no success dod i realize what could happen so i placed a big enough ball bearing in before i threaded the bolt in. And with 2 little zips of the impact everything came apart as it should.

So that stupid primqary chain guide is in and the crank reconected with the pistons. NOW i have the left outer piston(1) all the way down to place the cams in the right spot(hopefully) to get teh timing sqaured away so i can ride this thing eventually. Oh and quick wuestion the cam chain guide the one with the metalspring like baking plate, does the top of tha metal plate slide into a lil slot some where or does the cam chain just put tension on the top?

 

Hey Polock, to clear up a bit of confusion, WE are referring to the alternator shaft not the middle gear.

 

So,is that 2006 post possible or B.S.?

 

Yea pure B.S. i just removed that starter clutch the only way is to spli the cases. I mean u coukd remove the shaft without splitting the cases but that does no good cuz anything that would be broken would be inside still and no way to get it out. then it would falll down inside the block = alot of time wasted.

 

how did you get tht charging mechanism out?should I just pry it out with some flatheads or what? dont want to break anything. I do see the three torques behind it. I want to try to do this repair the same way you did. Since the motor runs and the only other issue it seems to have engine wise besides the same start issue you had all those years ago is it wont stay running and idle down. but after i get the starter clutch issue f fixed, im gunna run some fresh oil thru the case with some sea foam and see if that will get things runnin smooth

 

How did you get the charging mechanism out? Im at that point of the repair. And I can see the three torques behind it.

 

It's not possible to replace the starter clutch on our engines without splitting the cases. I have seen the seal being replaced behind the alternator rotor in fact there is a thread on here about it. But if anyone is changing their starter clutch split the cases.

 

What exactly are you repairing?
Please start a thread so we can focus on what you need for YOUR machine.

Alternator removal is covered here.
Replacing Alternator Seals in XJ700N with Pictures (applies to all XJ models)

 

If you are trying to get the rotor off the shaft, you need to tap on the shaft with a hammer (not too hard) and the rotor will pop off. Be prepared to catch it.

 

so I just put something in that hole? like a bolt and then tap it with a hammer? All these videos are saying to find a long bolt, thread it in a bit and tap it on the end. sounds like a similar process, but Im not having any luck.

 

Don't need to put anything in the hole.

A few taps on the end of the shaft has worked for me. Where the rotor sits on the end of the shaft is conical, so just enough of a tap to break it loose is all it needs. It will just kind of fall off.

I would suggest starting with a light tap, gradually getting harder until it falls off - shouldn't be anywhere near enough force to damage the shaft.

 

Can you assist me where to get a starter clutch and or parts I have a 1983 750 maxim which sounds like something is trying to escape my engine, than I have an 1982 750 seca I just picked up for $300.00 ,and the starter spins and 8 gear nothing engaging.

 

Welcome to the forum.

Check this first.

https://xjbikes.com/forums/threads/...building-your-slipping-starter-clutch.130438/

Len has all the parts you need contact him on info@xj4ever.com once you are sure.

 

See my post on the dreaded starter clutch , I have done two of these now . As far as parts yes xj4ever is best source , but I bought a repair kit off of eBay one was from England with heavier springs and drilled caps and new rollers. The other was a caltric starter clutch assembly.

 

A handy guide to not rebuilding your slipping starter clutch.

 

Hello well I've replaced a couple starter clutches on an xj750 maxim and a Seca both 1983 and I just pulled the engine, laid the engine on its back ,removed the oil pan ,clutch assembly cover as well as the the clutches and basket, on this side if the engine there is a flat retainer with 2 screws holding it,they need removed,on the left side of the engine there will be a small cover under the starter ,also with 2 screws in it this also will need removed.Once these are removed and the oil pan is removed you'll need a brass punch to push the shaft out of the the starter clutch assembly, just observe all pieces, oh it takes a little patience to put the new one in .