TTHJames Posted June 26, 2009 Share Posted June 26, 2009 I just replaced the chain and sprockets on my SR125 and did the brake shoes while I had the back wheel off. The brake shoes where tricky to get in but I was told it's normal for them to be quite tight. I put it all back together and started it up and the back wheel was stiff which I expected because the shoes where tight, so I gave it a bit of throttle thinking that it would loosen up, the back brake was as loose as it would go but still connected. And it did turn the wheel so I thought I'd take it up the road but when I started moving it stopped after a few feet and now there's no power getting the the back wheel. I can put it in gear and accelerate on the stand but the wheel doesn't move like it did before, the front sprocket doesn't even jerk like it would on the biting point if the wheel was seized, the power isn't getting to the front sprocket, I tried putting it in second and it's just the same. I'm worried I've screwed up the gear box by putting to much strain on it, or possibly the clutch, any ideas anyone? Cheers in advance, James. Link to comment Share on other sites More sharing options...
wild foamy Posted June 26, 2009 Share Posted June 26, 2009 if you cant hear any crunching/grinding sounds coming from the gearbox indicating a shredded gear, my guess would be on the clutch, it may be time to strip it down and check the plates over Link to comment Share on other sites More sharing options...
yoda Posted June 26, 2009 Share Posted June 26, 2009 Looks like the clutch doesn't like it. The rear wheel should be free to turn so if it isn't, file the leading edge of the shoes down until it turns freely. Link to comment Share on other sites More sharing options...
Moderator DirtyDT Posted June 26, 2009 Moderator Share Posted June 26, 2009 Have you fitted the front sprocket properly? I would not rev the b*ll*cks off it. If anything catches the bike will be up the road without you. Take the front sprocket cover off and with the bike in a high gear and the engine switched off push the bike. Does the output shaft spin ? (where you slid the front sprocket on to) If so the front sprocket is not locating. Link to comment Share on other sites More sharing options...
TTHJames Posted June 26, 2009 Author Share Posted June 26, 2009 There's no crunching so it isn't the gear box, thank god. I can let the clutch all the way out in first and second so I reckon that must be it. Also good idea about filing the shoes down, I thought about it but I thought they'd be alright once they were on and I didn't want to shorten their life. Is it a big job stripping down the clutch? I'm good with bikes but don't have much experience and I don't get my book of lies for another couple of days. Link to comment Share on other sites More sharing options...
TTHJames Posted June 26, 2009 Author Share Posted June 26, 2009 Have you fitted the front sprocket properly? I would not rev the b*ll*cks off it. If anything catches the bike will be up the road without you. Take the front sprocket cover off and with the bike in a high gear and the engine switched off push the bike. Does the output shaft spin ? (where you slid the front sprocket on to) If so the front sprocket is not locating. Yeah the sprockets definitely OK, I took the cover off so I could see if there was any movement at all, also I had it up on the centre stand so I wouldn't have gone straight into the field at the end of my driveway (there's a fence between me and it so that would hurt), I think it is probably the clutch but I'll check again anyway. Link to comment Share on other sites More sharing options...
Moderator DirtyDT Posted June 26, 2009 Moderator Share Posted June 26, 2009 Yeah the sprockets definitely OK, I took the cover off so I could see if there was any movement at all, also I had it up on the centre stand so I wouldn't have gone straight into the field at the end of my driveway (there's a fence between me and it so that would hurt), I think it is probably the clutch but I'll check again anyway. OK. Have a look at the link below as you have no manual. It is a 185 model but it may help! pick the part and zoom in. Here Link to comment Share on other sites More sharing options...
wild foamy Posted June 26, 2009 Share Posted June 26, 2009 not familiar with your bike, but on my DT its a case of undoing 3 allen screws to get the side cover off, letting the oil drain out of the clutch compartment and undoing 4 bolts to get to the clutch plates. on your bike the process would probably be similar albeit you will have more clutch plates (my DT has 2, but the Jawa has 5) Link to comment Share on other sites More sharing options...
TTHJames Posted June 26, 2009 Author Share Posted June 26, 2009 OK. Have a look at the link below as you have no manual. It is a 185 model but it may help! pick the part and zoom in. Here Thanks, that's a really helpful link. I read somewhere that if I lay the bike on it's side it will keep the oil in, is that worth doing or should I just let it drain out? Link to comment Share on other sites More sharing options...
Moderator DirtyDT Posted June 26, 2009 Moderator Share Posted June 26, 2009 Thanks, that's a really helpful link. I read somewhere that if I lay the bike on it's side it will keep the oil in, is that worth doing or should I just let it drain out? £10 for oil and fresh oil at that or scratches and marks with the possibility of something getting broken? Not a tough choice for me Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 26, 2009 Moderator Share Posted June 26, 2009 When replacing drum brake shoes you will often find a raised edge just before the shiny silver braking surface. This is residue from old shoes and water that has baked on the edge of the drum. If you do not remove this raised edge with emery paper when you fit the new shoes, they will catch on it and rock slightly on their pivots until the back edge contacts the brake drum. The upshot of all this is a wheel stiff to turn and at worst a cooked clutch. Fraid you better sort this out as well as your engine trouble. ...Paul Link to comment Share on other sites More sharing options...
TTHJames Posted June 26, 2009 Author Share Posted June 26, 2009 Thanks for all the help guys, I'm gonna sort it tomorrow , I just hope it's only the friction plates and not the steels that are shot. Also I had already figured out the thing with the brake shoe residue so I'm gonna sort that too. Cheers. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted June 26, 2009 Moderator Share Posted June 26, 2009 Thanks for all the help guys, I'm gonna sort it tomorrow , I just hope it's only the friction plates and not the steels that are shot. Also I had already figured out the thing with the brake shoe residue so I'm gonna sort that too. Cheers. Dont know whether you did this, but while the wheel and brakes are out, never miss an opportunity to grease the brake cam pivot that passes through the backplate Link to comment Share on other sites More sharing options...
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