Is my engine fully seized?

[Guest]

So I got an aprilia rs125 the other day and it cut out and wouldn't restart, I checked electrics cos it won't turnover at all then noticed water empty, shit...

Wen I push it with spark plug out it turns over quite easy wen pushing but randomly wen pushing it the back wheel locks, with the plug in it's a bit harder to push and if I try a proper bump the wheel locks most of the time, so I been told it sounds heat seized, hoping it's just a top end rebuild and the barels hopefully ok too, is it likely to be just the top end or the whole thing that's fkd, please ask any q's thAt I may not answered to help, thanks guys

[Colin the Bear]

Siezure is usually bottom end

[Guest]

Siezure is usually bottom end

Damn, any ways to tell without taking the engine apart, I heard heat seized was usually the piston expanding and messing the rings which can lock the wheel, wat else do u think it cud be locking the wheel, cheers mate

[Guest]

So I got an aprilia rs125 the other day and it cut out and wouldn't restart, I checked electrics cos it won't turnover at all then noticed water empty, shit...

Wen I push it with spark plug out it turns over quite easy wen pushing but randomly wen pushing it the back wheel locks, with the plug in it's a bit harder to push and if I try a proper bump the wheel locks most of the time, so I been told it sounds heat seized, hoping it's just a top end rebuild and the barels hopefully ok too, is it likely to be just the top end or the whole thing that's fkd, please ask any q's thAt I may not answered to help, thanks guys

the back wheel will lock as there is no weight on it, try bumping in the highest gear, if it locks thethe piston is seized and you would need a TOP-END rebuild, new piston, and rebore.. but been told previously that the RS clyinder is lined, so might need new sleeve... pm Fossie3000, he's a bit of an expert with the RS125, sort out the water issue, and check the bike over regularly...

P_O_W_D_E_R

Petrol

Oil

Water

Drive chain

Electrics (lights/horn etc)

Rubber (tyre pressures and tread)

[Colin the Bear]

Off the top of my head, crank bearings, big end bearing, little end bearing, piston siezed in bore. Hard to say from the info you've posted.

[Guest]

So I got an aprilia rs125 the other day and it cut out and wouldn't restart, I checked electrics cos it won't turnover at all then noticed water empty, shit...

Wen I push it with spark plug out it turns over quite easy wen pushing but randomly wen pushing it the back wheel locks, with the plug in it's a bit harder to push and if I try a proper bump the wheel locks most of the time, so I been told it sounds heat seized, hoping it's just a top end rebuild and the barels hopefully ok too, is it likely to be just the top end or the whole thing that's fkd, please ask any q's thAt I may not answered to help, thanks guys

the back wheel will lock as there is no weight on it, try bumping in the highest gear, if it locks thethe piston is seized and you would need a TOP-END rebuild, new piston, and rebore.. but been told previously that the RS clyinder is lined, so might need new sleeve... pm Fossie3000, he's a bit of an expert with the RS125, sort out the water issue, and check the bike over regularly..

P_O_W_D_E_R

Petrol

Oil

Water

Drive chain

Electrics (lights/horn etc)

Rubber (tyre pressures and tread)

 

Cheers man v helpful, here's the thing it splutters wen I try bump but won't start and won't turnover on the button, tried bumping in all gears and all times on random occasions wen I let go of the clutch dome times it turnsover for a while then locks and some times it jus locks, someone checked some cogs/ gears they cud spin with their hand and said there was no play so the bottom ends ok, does this sound legit,

If it is the top end wats causing the locking, Cheers guys

[Guest]

bumping a bike in gear will lock the wheel, unless you are sat on, are moving at a decent speed, (walking pace at least), If i bump start my bike (4 cylinders, i sit on it and get somone to push me... others run alongside and jump side saddle onto the seat at the time of dumping the clutch.. not recommended unless you know what your doing, bike could go over...

fix the coolant issue, and bleed the system or you'll have an airlock..

have you got a fully charged battery, and are getting a spark at the plug, do you have fuel, silly question, but if you forgot coolant...

charge the battery and try and start as normal,

if the piston was siezed then the bike would lock in all gears and every attempt, unless your bump managed to free the piston...

[Guest]

bumping a bike in gear will lock the wheel, unless you are sat on, are moving at a decent speed, (walking pace at least), If i bump start my bike (4 cylinders, i sit on it and get somone to push me... others run alongside and jump side saddle onto the seat at the time of dumping the clutch.. not recommended unless you know what your doing, bike could go over...

fix the coolant issue, and bleed the system or you'll have an airlock..

have you got a fully charged battery, and are getting a spark at the plug, do you have fuel, silly question, but if you forgot coolant...

charge the battery and try and start as normal,

if the piston was siezed then the bike would lock in all gears and every attempt, unless your bump managed to free the piston...

 

cheers mate, yea there is a spark checked that but only wen spinning the wheel, won't turn on the button tested battery fine fuel full, I believe that the coolant has been lost due to a bad gasket I've only had the bike a few days and it apparently had a rebuild 400 miles ago, so I rekon he sold it knowing, wat a mug I am, yea being pushed down a hill trying to bump in 2nd 3rd 4th it splutters a bit then the wheel locks, also even just wheeling it with the plug out I hear the piston moving in say 3rd then the wheel will lock, but how?

Thanks guys

[Guest]

Can random wheel locking wen pushing be caused by only the top end?

[Chrissb6]

Hi, finding no water in the system your probably looking at a piston seizure, bottom ends cranks etc, normally let go through lack of oil. Anyway to strip the motor down you have to start at the top so the head - barrel and piston is you first port of call. Take a close look at the piston - rings and the bore of the barral for any signs of damage. you can then inspect the crank for excessive movement of damage. Hopefully you get away with a top half rebuild.

Note on completion, double check your cooling system for the cause of the problem in the first place

best of luck

[Guest]

Hi, finding no water in the system your probably looking at a piston seizure, bottom ends cranks etc, normally let go through lack of oil. Anyway to strip the motor down you have to start at the top so the head - barrel and piston is you first port of call. Take a close look at the piston - rings and the bore of the barral for any signs of damage. you can then inspect the crank for excessive movement of damage. Hopefully you get away with a top half rebuild.

Note on completion, double check your cooling system for the cause of the problem in the first place

best of luck

Cheers buddy, I find out tomorrow, hopefully good news, if the barrels mildly scratched and I can get it cleaned up properly to I need to get it replated?

[Guest]

Hi, finding no water in the system your probably looking at a piston seizure, bottom ends cranks etc, normally let go through lack of oil. Anyway to strip the motor down you have to start at the top so the head - barrel and piston is you first port of call. Take a close look at the piston - rings and the bore of the barral for any signs of damage. you can then inspect the crank for excessive movement of damage. Hopefully you get away with a top half rebuild.

Note on completion, double check your cooling system for the cause of the problem in the first place

best of luck

Cheers buddy, I find out tomorrow, hopefully good news, if the barrels mildly scratched and I can get it cleaned up properly to I need to get it replated?

Also if it's scratched do I have to get it redone in nikasil, wat does nikasil actually do? I can get it honed for free but I cannot understand nikasil, cheers

[Guest]

You may want to ask here...

http://www.125ccsportsbikes.com/forums/ ... howforum=9

Nikasil http://en.wikipedia.org/wiki/Nikasil

Nikasil is a trademarked electrodeposited oleophilic nickel matrix silicon carbide coating for engine components, mainly piston engine cylinder liners. It was introduced by Mahle in 1967, initially developed to allow rotary engine apex seals (NSU Ro80 and C111) to work directly against the aluminum housing. This coating allowed aluminium cylinders and pistons to work directly against each other with low wear and friction. Unlike other methods, including cast iron cylinder liners, Nikasil allowed very large cylinder bores with tight tolerances and thus allowed existing engine designs to be expanded easily, the aluminium cylinders also gave a much better heat conductivity than cast iron liners which is an important factor for a high output engine. The coating was further developed by US Chrome Corporation in the USA in the early 1990s (under the trade name of "Nicom") as a replacement for hard-chrome plated cylinder bores for Mecury Marine Racing, Kohler Engines, and as a repair replacement for factory-chromed snowmobiles, dirt bikes, ATVs, watercraft and automotive V8 liners/bores.

Nikasil or similar coatings under other trademarks are also still widely used in racing engines, including those used in Formula One and ChampCar. Suzuki currently uses a race-proven nickel phosphorus-silicon-carbide proprietary coating trademarked SCEM (Suzuki Composite Electro-chemical Material) to maximize cylinder size and improve heat dissipation, e.g., on the engine of the Suzuki_TL1000S and Suzuki DL650 V-Strom and Hayabusa motorcycles [1].

Engines using Nikasil:

Aprilia RS125 And Aprilia SX/RX 125

etc, etc, etc, etc,

[Guest]

^^^^^

cheers bro, I did try researching it but just kept coming up with random things,

So basically it creates less friction, which in turn means less heat and less wear,

Seems expensive though,

Thanks again

[rollazuki]

If it locks up intermittantly Id guess maybe a couple of things:

Piston broken/cracked, and catching on the edges of the ports, would be hellish noisy tho when it did spin over.

Possible bottom end seizure, maybe bearings in main bearings misplaced, or possibly a damaged or cracked gear in the primary drive.

One other thought, where has all the coolant gone?? if the base gasket or head gasket has failed, all the pretty green coolant may well be sitting in the bottom of the engine, causing the primary compression to be huge, and stopping the motor spin over.

Quit guessing and pull the head and barrel off, its maybe 2 hours work, and will reveal the extent of the problems.

[Chrissb6]

Hi, I would not try and run it again until you have stripped it down and taken a look.

There is a possibility that, you might have a broken piston ring, a piece of this could drop in to the crankcase and make the job a hole lot more expensive. If the barrel is nickleseal coated l would of thought you would be looking at a replacement barrel piston and rings, would also suggest fitting new little ends for peace of mind. I use to know of a small machine shop in Notts that use to machine the barrels out and insert a steel liner should you find you cannot find a replacement at the right price, note: if you barrel is scratch or scored you have no chance at all of cleaning it up it will have to be replace or machined. Dont cut corners, it just not worth the time and agro

[Guest]

Top and bottom end seized, wat a mug off, new engine job, hope the geezer I bought it off has got some temporary sealant left cos he's gonna need it wen I break his legs tonight

[Anthony]

Your bike >>>>

The dude who you bought it off>>>>>

What you do to him

[Guest]

Thanks to all for ur help, last question

Can u estimate in kg the weight of a boxed aprilia 125 engine, I need to know for the delivery form cheers, I'm guessing 30kg

[Guest]

does the courier have bracket weights

0-10kg

10-20kg etc, just figure out the most probable...

looking at one for sale on ebay the carriage is £35 with parcelforce 48, which is what they charge for 30Kg UK-UK

[Colin the Bear]

Has an odour of male bovine excrement slowly percolated through.

[Guest]

Lol at some of the last few, cheers for the info regarding my questions, should be runnin in the nex few days, this new engine apparently still needs running in, any ideas?

Under 6k rpm for 500 miles or am I way off