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The TTR250 FAQ web pages -> TTR250 -> Repairs and maintenance -> right then , this sprag clutch "BANG"
Post Info TOPIC: right then , this sprag clutch "BANG"
nelly


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right then , this sprag clutch "BANG"
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hi guys and gals

I'm sorry to have to bring this up yet again,

as you may or not know, I'm a newb to this site, but not to bikes in general,

when we bought our lads 95 ttr , I was prepared to have to do the spag clutch, and it did indeed  have the dreaded bang when turning off, sounds a bit like smacking the vice with a hammer, SO today ,with the pictorial how-to,so kindly posted,i set about investigating, everything came off as it should, I inspected every part for wear , nothing , I dissembled the sprag and its perfect,no breaks or wear, anywhere, what I did notice is the starter motor seemed loose, as I started to try and tighten the 7mm bolts,[ the 2 that go the length of the starter]

it very slightly moved the starter off-centre,[ they were quite loose ] left bolt pulled it left and right pulled it right, I only turned each one 1 turn before the starter spindle became too tight to turn by hand, I HOPE YOUR WITH ME UP TO NOW,so I loosened them off again, but the starter was loose, not rattly loose but loose as if it was rubber mounted,anyway I re-assembled  and properly torqued everything and the BANG is still there, could the BANG be something to do with the starter, I'm not sure if its even the correct one,but I'm 99% sure that the sprag clutch isn't the problem,but as always I'm happy to be corrected, btw,

if I hold my hand on the starter motor itself whilst I hit the button it seems very rumbley [ is that even a word ],

thanks in advance nel



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TTRfan


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Wear on the sprag clutch teeth is not always obvious but the bang indicates it's at fault.

As the "how to" guide suggests, also check the boss that the sprag runs on for wear/damage.

A loose or misaligned starter motor wouldn't cause a bang on shut off. That's a different kettle of mechanical fish!

If the bang has been happening for a while it is highly likely that some collateral damage has been caused at the starter end cry

Hope that helps.

Brian



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jasparach


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Hi, maybe i missed it in your post but did you replace the sprag
with a new one? If the bang was there with the old one and you
just reinstalled it again then the bang will still be there as it is not
possible to see the wear in them. It is possible that the roughness
in the starter is down to bearings worn in the starter body itself.
If you can post a picture of the starter someone will be able to tell
if it is the correct one fitted.

John

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nelly


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thanks guys

no I didn't fit a new sprag, as it "looked" perfect to me, theres no damage or wear on any of the other gears,components,the starter is bugging me more now,

I will buy a new sprag and get it fitted very soon, should be easy next time, now I know what I'm doing with it

the starter works ok but its noisy, but its the movement in it that's bugging me, I think its been messed with somehow,and maybe theres some shims or spacers in the wrong place,

surely I should be able to tighten the two 7mm headed bolts without it all tightening up and stopping it from spinning ????

also when I order the sprag il get a speedo magnet too,the speedo works on/off, and when inspecting the magnet I found its broke clean in half, I bodged it together with some araldite to stop it spinning in the washer and it worked for a couple of days, but found today that its spinning again, tell you what though I really the bike,so much in fact that I'm going to sell the 04 fazer and get one for myself,preferably with a kicker lol

il try and get a pic of the starter up tomoz

thanks again

nel



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jasparach


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The starter should not tighten up if the correct washers and the
bearings are in good condition. It is possible that it has been opened
already and maybe that is the cause of the problem. There is a thread on the
starters and what it can be replaced with here.


ttr250.activeboard.com/t48824180/starter-motor-problems-and-solutions-megathread/

 

There are a couple of alternatives for the starters  in the thread.

 

John



-- Edited by jasparach on Sunday 13th of September 2015 07:34:41 PM

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TTRfan


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nelly wrote:

I bodged it together with some araldite to stop it spinning in the washer and it worked for a couple of days, but found today that its spinning again,

 Odd though it may seem, the original magnet will spin between the washers confuse



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nelly


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thanks guys

and brian, so the magnet should be free spinning in between the washers, well it sure is odd that the speedo worked at all then,
no harm done this time hey, hopefully it should be ok when I fit a new magnet,

jasparach , thankyou for the link much appreciated

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TTRfan


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Slight amendment on the magnet spinning business!

I have two good original magnets here. On one of them, the magnet is fixed between its adjacent washers but moves freely on the spindle. On the other one, nothing moves confuse

It has been my experience with other magnets that there is movement.

If your magnet was only in two pieces and you Araldited it together then it should have worked. If it doesn't then maybe the problem is the sensor?

Brian

 



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mossproof


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The starter motor is held TOGETHER by the 2 7mm headed bolts running along it's length, but is held IN POSITION by 2 10mm headed bolts which screw vertically down into the lower engine casing (Right hand end of the motor). (Sorry if I'm teaching granny to suck eggs!) The other (left hand) end of the starter motor locates into a hole in the outer flywheel case using an o ring to take up the slack in the fit. If the 2 10mm bolts are tight, I assume the movement is in the body of the motor, which would suggest to me some missalignment and possibly a stripped thread somewhere which is not allowing the starter motor body to tighten up properly. I would at least take the motor off to investigate fully, maybe take to a specialist to take a look if necessary - I use Stones Auto electricians in Kidderminster, who are excellent, but I haven't checked your profile to see where you are...
Good luck,
Simon.

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nelly


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thanks simon
I will remove the starter soon, whilst I replace the suspect sprag clutch,and double check all the gears involved, [ when our lad comes up with cash for the parts ] ,he cant ride it yet anyway ,hes currently taking the course for his a2 licence,so ive got plenty of time to get it fixed properly,
il probably look into the 250 majesty starter as a replacement,swapping over the mounting bracket shouldn't be a problem. [ but does anything ever go to plan ? ]

your help is much appreciated thankyou
I'm in Nottingham btw,
nel

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