gearbox problem me thinks?

[willybob1987]

hey guys im new the BCF but i have abit of a problem with a bike iv just brought. imade the mistake of not taking it 4 a long test drive bt whilst on my way home on it (35miles) i noticed quite a loud whining/grinding noise when its excelorating through all the gears but seems to go in 5th at around 60ish and is even worse when im slowing down through the gears. wen i pull the clutch the noise stops and its fine. im thinking it mite b the clutch or summets a little loose in the gear box but not sure. any ideas?

any suggestions wud b wicked
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W, Mulvey

[Chriss]

Details about the bike would be useful.
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TheShaggyDA: I've got 3 or 4 pairs that predate my wife, so at least 11.5 years old.

[iooi]

I would have a look at chain/sprockets first.

Could be dry chain or knacked front sprocket.
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Just because my bike was A DIVVY, does not mean i am......

[Chriss]

[FirebladeRuss]

If you're coasting, there's no tension on the chain or sprockets though
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Twitter is for people who can't STFU even when they're by themselves

[N cee thirty]

imma guessing the chain will be as dry as a nuns fanny

get it lubed
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'00 Aprilia RS50 > '92 Honda CG > '99 Yamaha Fazer > '91 Yamaha RXS > '79 Suzuki X5 > 01' Honda Cg > 07' Honda Cg > 82' Kawasaki Z200 > suzuki gsxr 400 gk73a > honda vfr 400 NC30 Mod 2 Passed 09/06/2011

Jewlio Iglesias wrote: I actually did vote BNP once

[Rogerborg]

Yup, sounds like an over-tight or dry chain, but treat the beastie to an oil and filter change as well.
____________________
Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[willybob1987]

hi people thanks for the replies and my appologies for the lack of info. its jst a giantco 125 4stroke. its only dne 9k. iv had a luk at the chain and sprockets and they r a little worn bt not too excessive. i cn tell straight away that it needs an oil change so i brought some fully synthetic oil but then read on 1 of the other posts that its not a gud idea to use fully synthetic as it can cause the clutch to slip?
also 2 add sumthing else i forgot, the gear change has ALOT of travel before it selects the gears and i mean ALOT!!! could this b one of the causes? thanks for the info so far and plz keep them coming
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W, Mulvey

[Chriss]

I had to Google who Giantco was as I'd never heard of them. I found the source of your problem.

[Frost]

[iooi]

What sort of linkage has the gear change got ? Many bikes have a lot of travel before they go into gear.

As to sync oil. Should be OK. Only oil to avoid is one that has friction additives, such a magnatec. As that will stick to clutch plates.
But people do use it with no issues.....


A quick tip.

Your on a forum, no need to use text speak in posts.... Makes it hard for us oldies to understand
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Just because my bike was A DIVVY, does not mean i am......

[willybob1987]

well that made me feel even worse so thanks frosty lol.

sorry for the text speak iooi its force of habbit.

well atleast i dont have to buy some more oil now atlest.

chriss i couldnt figure out what your link was about because i followed it but it just took me to the giantco website. so what is the source of my problem then mate?

i only paid a couple of hundered of quid for it so i dont mind spending abit of money getting it sorted.

oh and just for the record its the hunter city. if that makes any difference?
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W, Mulvey

[ThoughtContro...]

[willybob1987]

right ok then but now iv hit a slightly bigger problem
the bloody engine wont turn over. all i did is an oil and filter change, tighten up the engine mountings. noticed abit of play in the front sprocket so i tried tighten it up. thought nothing more on it could have ben done but when i finished it wouldnt turn over?!?! any clues please?!?!
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W, Mulvey

[paddlesat16]

yup, you touched something on the bike that use elektrickery, and it don't like it check your electrical connections and earths on the bike.
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I once saw a bloke shagging a donkey.... in Saudi arabia. Theory Test Passed 26/10/09 Mod 1 Passed 26/4/10, Mod 2 Passed 7/6/10 Current Bikes Suzuki GSX1400 K5, Aprillia Pegaso 650, Suzuki DR350T.

[willybob1987]

sorted! it had just locked into 2nd. rocked it gently back and forward and job done. might get it looked at propperly tho. panic over lol. well i started it up and it sounds so much smoother and healthier. going to fill it up with super unleaded and put some redex in with it and give it a good run within the nex day or 2. will keep you all posted. off to bed now as im at work tonight lol.
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W, Mulvey

[Rogerborg]

There'll be a bit of movement in the front sprocket because it's bolted to a clip on the spline rather than being secured to it directly. This is normal.

This yours?

https://www.bikez.com/pictures/giantco/2008/28890_0_1_2_hunter%20city125_Image%20credits%20-%20Giantco.jpg

I'm sure someone can identify what it's copied from.

The engine looks to be a 156/157FMI unit, a fairly close copy of the Honda CG125's engine. When you say "filter change", did it actually have a replaceable filter, or is there a mesh filter fitter horizontally on the bottom left hand side?

It sounds like your problem is at the bottom end, but it'll also want the valve (tappet) clearances checked regularly. It's a fairly simple job, so I suggest that you do that now. You'll need a set of feeler gauges. The procedure is described here and here.

These engines tend to be pretty robust. Sling any old oil in them. I've used semi and fully synthetic, and even dumped some Activ-8 friction reducer in without causing clutch slip: that's not a recommendation, just information.

Just be cautious about handing it to a garage to deal with. Once they get into the engine, it can easily cost you more than the bike's value. If it turns out that the gearbox is shagged, then you may be as well trying to find a replacement engine from another bike.

And bear in mind that you'll never recoup anything that you spend on it, so only spend what you can afford to lose.
____________________
Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[ThoughtContro...]

[willybob1987]

hey rogerborg yeah thats the bike iv got.
i had 1 similar but it was styled as the older shape cg and it was cooland the only reason i havnt got it now is because some sticky fingered little c+#t knicked it. i was going to order a set of feeler guages anyway so then i dont have to borrow my cousins. the oil filter is 1 of those steel mesh types but i cleaned that with some stuff i "borrowed" off my cousin lol. im going to check all of the cables anyway just to be on the safe side
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W, Mulvey

[willybob1987]

i dont suppose anyone knows what spark plug it needs do they?
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W, Mulvey

[Chriss]

Take your old one out, it should have the details printed on it.
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TheShaggyDA: I've got 3 or 4 pairs that predate my wife, so at least 11.5 years old.

[willybob1987]

right well i took the bike out today and it rides like a dream BUT the noise is still there although its not quite as loud, it is still there. what needs to be done to check the clutch and surrounding areas?
really appreciate the feedback and help so far guys so thanks
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W, Mulvey

[Chriss]

There's a how to written recently for small Honda's! See if this help. Trying to find a service manual for your specific bike will be difficult.
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TheShaggyDA: I've got 3 or 4 pairs that predate my wife, so at least 11.5 years old.

[willybob1987]

this looks about right and i think i will get a new clutch kit for it as well as a new chain and sprocket set for it. only problemis that im really struggling to find places that do parts for my make? will honda cg stuff go on it i,e, clutch kits and chain+sprockets? thanks guys
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W, Mulvey

[willybob1987]

also was thinking of replacing the exhaust too as its abit rusty and rattly. iv seen one off a 2006 sanya sy125 which luks pretty much identical to mine but will that fit?
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W, Mulvey