b*gger revisited

edarter · Post by **edarter** » 31 Jul 2005, 21:56

Hey all, I have FINALLY managed to get the time to pull the left side cover off the motor to check the main bearings as per the advice given in 'b*gger' thread. Absolutely no play on the main bearings but there is a bit of play in the balance shaft - probably 0.5mm+ I'm assuming this is not good and that this is probably whats caused the noises that the mechanic heard at the MOT. Assuming this - does it still mean a complete engine strip down to do the balance shaft ?

Thanks

Ed

Harry Carter · Post by **Harry Carter** » 01 Aug 2005, 00:16

that doesn't sound good.

Bargos · Post by **Bargos** » 02 Aug 2005, 09:44

Ed,

When you withdrew the balance shaft was there any heavy scoring on it?

Mine started making 'odd' noises from the clutch over two years ago - I started fretting about it, pulled the clutch and balance shaft apart and couldnt find anything wrong.

Ive been riding the bike for the past two years with no problems at all.

Let me know.

B.

edarter · Post by **edarter** » 03 Aug 2005, 13:15

haven't withdrawn it yet bargos - may get to that tonight though. I have the clutch side casing off but can't yet make out how to get to the back end of the balance shaft. May all become clearer when I get the kick start mech and clutch out of the way...

Bargos · Post by **Bargos** » 03 Aug 2005, 13:39

Ed,

If memory serves you need to remove the gear from the end of the crankshaft (the one that drives the basket of the outer clutch. The balance shaft sits beneath that and will pull straight out. When you put it back in make sure that you line it up correctly - there are marks to enable you to do so.

Let me know how you get on.

B.

d5aul · Post by **d5aul** » 03 Aug 2005, 20:02

I replaced my Balance shaft & bearings a while ago, I did not have to remove the Crank gears, just had to remove the clutch basket & then undo the nut on the end of the Balance shaft & the shaft slides out, mine did have scores on the bearing surface at the flywheel end!

The following link is available from the CRM250.com home page & details an engine removal & strip etc!

http://www.offwidth.co.uk/bike/crm_rebuild/

Bargos · Post by **Bargos** » 04 Aug 2005, 09:40

Ah yes thats right, it becomes clear once you take a closer look!

edarter · Post by **edarter** » 04 Aug 2005, 12:44

yeah - thats the one I am using to help with the strip down. Could not get the chuffin flywheel bolt to let go last night though ! Followed his instructions to wedge a bar in the rear sprocket but no joy. Phoned the local bike shop today to see how much they would charge to get that nut off, remove flywheel and the crank primary gear nut and they said 'tea money mate - just pop it down' result !!!! will be taking it to them to do this bit me thinks.
Have to admit - the further I'm going the more nervous I'm getting about managing to put it all back together right - really not looking forward to the gearbox stuff

d5aul · Post by **d5aul** » 04 Aug 2005, 19:11

From memory, the flywheel does not need to come off!

edarter · Post by **edarter** » 05 Aug 2005, 13:17

oh well - never mind - nuts all loosened off nicely now !

One VERY strange thing though. Took the thermostat housing off and there was no thermostat !!!!!!

anyway - tune in soon for the next exciting install of 'Ed buggers his engine', there will be a follow up series called 'where the fek did that bit come from'

Harry Carter · Post by **Harry Carter** » 05 Aug 2005, 20:35

edarter · Post by **edarter** » 08 Aug 2005, 13:24

hmmm....pants !!!! what a weekend, firstly couldn't undo one of the hex head bolts to get one of the flywheel pickups off. A mate has some tools called 'easy out' or something, anyway - drilled into the centre of the bolt and wind in this thing with a reverse thread. This basically tightens into the bolt the more you do it up, but in the direction of the bolt being undone ! popped out really easily then. Then we checked out the con rod - noplay if you push and pull, but htere is a sideways wobble (as opposed o being able to slide the whole conron on the crank) I reckon the wobble is about 1-2mmat the little end...me thinks big end may be on the way out

Bargos · Post by **Bargos** » 11 Aug 2005, 20:24

Ed,

Fret not! You should get a tiny bit of side to side movement - its perfectly normal. You should only worry if there is play in the other plane, i.e. the top to bottom direction of the conrod itself. Did you check the balance shaft as I suggested?

In fact, why not go the whole hog and repeat what is wrong with the bike please...

edarter · Post by **edarter** » 12 Aug 2005, 12:50

Hi Bargos - sorry, not been about for a few days.
Right- whats wrong with the bike - well not sure really, went in for an MOT and the guy said the engine sounded very ropey and that it sounded like main bearings, e is known locally as a bit of a 2 stroke whizz so took the advice at face value in the end. Having spoken on here about whether it could or couldn't be I thought bugger it, the peace of mind has got to be worth a strip down of the engine to check everything out. anyway.... no play on the mains (though LT say that doesn't necessarily mean they are not shot) a little play on the balance shaft (though no marks on the shaft itself) and what I've described above on the big end (need to re-check the little end as I can't remember but think there was no play on that). Not actually split the case halves yet as I'm still recovering from when I pulled the gear change mech off and it all fell apart - MAJOR panic as to how the pawls etc all fit in there !!! Think I have it sussed but now a little scared of when all the gearbox bits drop out !!!! Th crank feels smooth enough as I rotate it but who knows - I'm hardly puttign the same load on it as when it's in use am I......

d5aul · Post by **d5aul** » 12 Aug 2005, 14:11

Ed,
I would be inclined to take the bits to your MOT tester & ask him to have a quick look, if he is as good as people say, he should be able to tell you what is wrong!
He may not be awear that the CRM has a Balance shaft as very few 2 strokes have them.
If you have play in the Balance shaft I would look at replacing the balance shaft & bearings!
If you have gone to the trouble of removing the engine I would be tempted to replace the main bearings anyway, I do not think the Mains are too expensive!