GT125 Hard to start and little smoke on cold

[Alex]

Assume that needs an engine rebuild in very soon time

i didn’t check the compression yet and spark plugs as I got this bike just yesterday

it’s 16 plate 9500 miles on it, seems as previous owner was really riding like a twat on this bike as oil seems old and no oil on chain at all

is there is any workshops around South Yorkshire and if you can give me postcode?

[♠️ M77]

Not around South Yorkshire that I know of  , but you can email us using “CONTACT” link at the bottom of the site as we do fix these up every month.

Welcome to the club though!  = Stick with her, will be a nice fun machine for the summer once everyhing gets going.

[Alex]

So after 5 days of owning it, It’s seems to be working fine when warm. I don’t have enough money right now to buy all the filters and compression check tool, I will get paid on Friday and order all of the filters and will get to the carbs to see what’s going on.

so main problems right now is. 5 am in the morning about 5-8 degrees, it’s quite hard to start up, but with choke on and almost full throttle it starts.

rear cylinder seems to be always more colder than front one and when engine is cold I can clearly feel that one cylinder doesn’t fires up until 4k rpm

i use it daily to get to work and back, when I start it up at 2:30 about 13 degrees outside it’s start ups fine without choke but giving it a throttle

there is actually no smoke from exhaust so it’s might been just steam

Oil level stays in same position so it’s not going anywhere , so I don’t really think there is problems inside engine but I will anyways check compression later and will update you

and also just as temporary I put inside that wynns thing in fuel tank to see if it will change anything before I will get everything

and last bit! I’m not sure if it’s a really something but it smells quite more than should be with petrol from exhaust but it’s black widow exhaust without baffle fitted on

im not English (sorry for mistakes if there’s any :))

[Alex]

So, I got to the air filter just to see what’s going on

that’s funny but, is there is any place where I can get new pistons and rings?

front cylinder fucked up

Front cylinder spark plug full in oil, smells with petrol inside engine, oil and petrol in air filter

needs an engine rebuild… spent grand on this bike 👍

[♠️ M77]

Yes,  check my ebay https://www.ebay.co.uk/usr/evocrest for used parts

Sorry to hear that,  but be sure and test compression on both cylinders if you can after the engine is warmed up ?

She is still alive and you still riding but ofcourse a rebuild will make it last longer hopefully since the previous twats clearly have abused the bike by the looks of it.

If you’re adamant for a new piston or rings,  email us and tell us if its for front or rear and ill get it locally

Don’t bother with the “hyosung websites” that are blue & white , you will be back next week calling your bank for refund or fraud issues.  There is posts about it on this forum anyway.

We still don’t know if its engine pistons  or  maybe cylinder valve has worn “oil seal”    like these

Engine Valve Stem Guide Oil Seal (x4 Seals) – Various Hyosung Models

Because spark plug is directly between the 4 valves also.  As soon as valve opens,  it is possible a tiny bit of oil goes on the plug causing boggy runs (oily plug hard to spark, so it is stressed to keep sparking your engine)

Your ideas for replacing air filters etc are not a bad idea.

Last thing,  when you ride on a private road or somewhere very safe to do so,  ride up to 10,000 rpm, then look at mirrors, do you see smoke ?

When bike is hot ,   rev it to 5,000 when it is standing on idle ,  and let go of throttle , do you see smoke ?

Open the “FILLER” CAP for the oil on the clutch cover = smell inside , do you smell fuel ?  ==> Maybe carb floats and float needs have burst open  (replace them) because they may be leaking fuel in to the cylinders  =>  causing piston walls to dry up instead of staying oil coated, so the fuel ends up in the engine crank etc == > Replace oil with motul 7100 and replace oil filter too!

[Alex]

Well day was hard but I did it!

I took whole engine off the bike lol

i don’t mess up riding it until it dies 🙂

so, carbs absolutely needs cleaning and replacing (or upgrading jets and all of that)

I will take the head out tomorrow and see what’s going on with rings and piston it’s front one

i will get seals and all of new engine gaskets anyways to make sure and keep it going as I need it daily for next few years (haha)

and yes it’s smells petrol inside oil cap

[Alex]

I didn’t see any smoke at 10000 rpms as I remember honestly, I did rev it on neutral but didn’t see smoke last days but what I do remember is when I was buying this bike, when the guy started it up I’ve seen a bit of smoke come out of exhaust but I didn’t gave it a reason for it to be smoke as it was about 8 degrees so might was just steam, same as in rainy weather.

I will keep you updated tomorrow. I’m really lucky to have you here Marcel! Thanks.

 

[Alex]

[Alex]

This is what I found when was taking out oil from engine (this is magnetic oil drain plug)

[Northman]

Alex wrote:

Esto es lo que encontré cuando estaba sacando aceite del motor (este es un tapón de drenaje de aceite magnético)

Citar

OMG… You need an engine flush urgently

 

[Author]

Posts

[Alex]

Assume that needs an engine rebuild in very soon time

i didn’t check the compression yet and spark plugs as I got this bike just yesterday

it’s 16 plate 9500 miles on it, seems as previous owner was really riding like a twat on this bike as oil seems old and no oil on chain at all

is there is any workshops around South Yorkshire and if you can give me postcode?

[♠️ M77]

Not around South Yorkshire that I know of  , but you can email us using “CONTACT” link at the bottom of the site as we do fix these up every month.

Welcome to the club though!  = Stick with her, will be a nice fun machine for the summer once everyhing gets going.

[Alex]

So after 5 days of owning it, It’s seems to be working fine when warm. I don’t have enough money right now to buy all the filters and compression check tool, I will get paid on Friday and order all of the filters and will get to the carbs to see what’s going on.

so main problems right now is. 5 am in the morning about 5-8 degrees, it’s quite hard to start up, but with choke on and almost full throttle it starts.

rear cylinder seems to be always more colder than front one and when engine is cold I can clearly feel that one cylinder doesn’t fires up until 4k rpm

i use it daily to get to work and back, when I start it up at 2:30 about 13 degrees outside it’s start ups fine without choke but giving it a throttle

there is actually no smoke from exhaust so it’s might been just steam

Oil level stays in same position so it’s not going anywhere , so I don’t really think there is problems inside engine but I will anyways check compression later and will update you

and also just as temporary I put inside that wynns thing in fuel tank to see if it will change anything before I will get everything

and last bit! I’m not sure if it’s a really something but it smells quite more than should be with petrol from exhaust but it’s black widow exhaust without baffle fitted on

im not English (sorry for mistakes if there’s any :))

[Alex]

So, I got to the air filter just to see what’s going on

that’s funny but, is there is any place where I can get new pistons and rings?

front cylinder fucked up

Front cylinder spark plug full in oil, smells with petrol inside engine, oil and petrol in air filter

needs an engine rebuild… spent grand on this bike 👍

[♠️ M77]

Yes,  check my ebay https://www.ebay.co.uk/usr/evocrest for used parts

Sorry to hear that,  but be sure and test compression on both cylinders if you can after the engine is warmed up ?

She is still alive and you still riding but ofcourse a rebuild will make it last longer hopefully since the previous twats clearly have abused the bike by the looks of it.

If you’re adamant for a new piston or rings,  email us and tell us if its for front or rear and ill get it locally

Don’t bother with the “hyosung websites” that are blue & white , you will be back next week calling your bank for refund or fraud issues.  There is posts about it on this forum anyway.

We still don’t know if its engine pistons  or  maybe cylinder valve has worn “oil seal”    like these

Engine Valve Stem Guide Oil Seal (x4 Seals) – Various Hyosung Models

Because spark plug is directly between the 4 valves also.  As soon as valve opens,  it is possible a tiny bit of oil goes on the plug causing boggy runs (oily plug hard to spark, so it is stressed to keep sparking your engine)

Your ideas for replacing air filters etc are not a bad idea.

Last thing,  when you ride on a private road or somewhere very safe to do so,  ride up to 10,000 rpm, then look at mirrors, do you see smoke ?

When bike is hot ,   rev it to 5,000 when it is standing on idle ,  and let go of throttle , do you see smoke ?

Open the “FILLER” CAP for the oil on the clutch cover = smell inside , do you smell fuel ?  ==> Maybe carb floats and float needs have burst open  (replace them) because they may be leaking fuel in to the cylinders  =>  causing piston walls to dry up instead of staying oil coated, so the fuel ends up in the engine crank etc == > Replace oil with motul 7100 and replace oil filter too!

[Alex]

Well day was hard but I did it!

I took whole engine off the bike lol

i don’t mess up riding it until it dies 🙂

so, carbs absolutely needs cleaning and replacing (or upgrading jets and all of that)

I will take the head out tomorrow and see what’s going on with rings and piston it’s front one

i will get seals and all of new engine gaskets anyways to make sure and keep it going as I need it daily for next few years (haha)

and yes it’s smells petrol inside oil cap

[Alex]

I didn’t see any smoke at 10000 rpms as I remember honestly, I did rev it on neutral but didn’t see smoke last days but what I do remember is when I was buying this bike, when the guy started it up I’ve seen a bit of smoke come out of exhaust but I didn’t gave it a reason for it to be smoke as it was about 8 degrees so might was just steam, same as in rainy weather.

I will keep you updated tomorrow. I’m really lucky to have you here Marcel! Thanks.

 

[Alex]

[Alex]

This is what I found when was taking out oil from engine (this is magnetic oil drain plug)

[Northman]

Alex wrote:

Esto es lo que encontré cuando estaba sacando aceite del motor (este es un tapón de drenaje de aceite magnético)

Citar

OMG… You need an engine flush urgently

 

[Author]

Posts