Starter question

I have a 83 xj900 that is making a grinding sound sometimes when I try and start it. It sounds like when a Bendix is going out on a car starter. Do I need to replace the starter or can I rebuild it?

 

They can be rebuilt, take it apart first to see if anything is dammaged. If there is severe wear or dammage to the bearing surfaces or the starter commuator, toss it and find another. EBAY is a good source for used parts, or a local cycle salvage yard. If you go for the used starter , be sure to take it apart and clean ond/or replace bearings and brushes. PM Chacal can supply you with the right parts. I think the XJ900 and XJ750 starters are the same , but not sure.

 

I have a xj750 can I swap these starters?

 

Yes, XJ650/700/750/900 starters are all the same, although some are painted black, only differences are that some have a natural finish on the case and end coverm while others are painted black.

 

You might also be seeing the beginning symptoms of a starter clutch issue, which can be caused by worn or failed parts or simply the wrong oil.

 

I was reading about the oil issue and wonder how using Synthetic can cause these problems? It is like it isn't engaging with what ever is turning the engine. The starter spins and make horriable sounds then if I let go of the starter button and try it again it will catch and turn over.

I guess I am going to try and change the oil I just put a new filter on it not a week ago when I filled it with fresh Amsoil. Do you think that the filter will be fine?

 

Well I rode to vintage motorcycle days last week and the problem started getting worse so I decieded to try the oil change, I cant belive that it worked. Still confused why Synthtic is the cause of it but who cares it worked thanks.

 

Drauff, the clutch works with rollers, when turned in one direction they get tighter, friction & wedge. Glad the oil sorted it 'cos if the outer race cracks it's a major job to replace the clutch.

 

Synthetic oil caused the issue because it's too slippery and the rollers (see Wiz' illustration) can't "bind up" and lock the races together.

Common issue, which is why I mentioned it.

Between the starter clutch and the bike's wet clutch, your best bet these days are oils specifically made for motorcycles.

 

My 900 can't handle synthetic oil, but my 750 can.

It varies from bike to bike.

 

THAT'S interesting, seriously. Starter clutch-wise, or are there other factors behind your statement?

If just the starter clutch, I wonder if it's a difference in wear (or lack of it) of the associated parts. How many miles on each bike, out of curiousity?

 

The 900 has over 44000 miles. I was using motorcycle synthetic oil with no friction modifiers.

 

i would say chipped teeth on the flywheel and starter.

synthetic oil makes a big difference in motorcycles. install regular motor oil and bikes do some strange things. transmission hard shifts will be one of them. specially when it fights to go into neutral.

although. seems like the newer bikes don't matter.

 

snowwy look at Wiz' diagram. There are NO teeth on a flywheel, this isn't a car. No gear sliding back and forth trying to engage teeth.

It's a "sprag" clutch, and the synthetic oil was causing the problem.

The mileage on the bike leads me to believe that a combination of synth oil and worn (maybe not so much worn as polished smooth) parts in the starter clutch caused the issue.

I'm interested to see TIME'S response, if it's a high mileage bike that doesn't like it and a low mileage bike that doesn't care.

Or maybe I'm completely off base, which is why I asked.

 

[quote="bigfitz52
I'm interested to see TIME'S response, if it's a high mileage bike that doesn't like it and a low mileage bike that doesn't care.
[/quote]
I put AmsOil 20W50 Motorcycle Synthetic in the 900 at 25,000 miles and immediately had the "goose honk" starter. I even drove it awhile by bump starting, hoping it would get better. I've been running a blend of Rotella T (mineral), Castrol GTX,(mineral) and Mobil 1 and it likes it.
Showing 30,000 awesome miles.

The '81 Seca 750 has had Mobil 1 or AmsOil for 3 years. No starter clutch issues. The regular clutch has always slipped just a bit.
Now at 47,000 satisfying miles.

 

Time, the mineral oils you are mixing, are they the same viscosity?

 

No, the Rotella is 15W40
The rest is 20W50
I don't buy 10- weight oil anymore.

And - I've heard that the additive package of one oil will "attack" the additives of another brand. It's working for me.

 

Time, it is my understanding that you can mix brands of oil, but not the vicosity.

 

Didn't want to go this far off topic, but what the heck- -
What have you heard about blending different viscosities, Wizard ??

 

The denser oil will go to the bottom of the motor & the ambient temperature can exacerbate this phenomenon.

 

As long as it's all the same TYPE (conventional vs. synth) won't it mix and stay mixed? What would cause it to separate again?

Now I gotta get Googlin' I never heard of that before.

 

Crude oil came to mind when I read that. Sure, not the same, but - -
the different weights of hydrocarbons seem to stay blended after sitting for 65.5 MILLION years, or more.

Even the Propane stays dissolved and blended, along with Asphalt and everything between, from what I've heard about crude oil.