shitty nsr problems please help

[lee125]

hi im pissed off at the moment about my f**king shit nsr right ok well its always been running a bit hot about half way up the gauge most of the time and now its getting to the red and its spitting out all the coolent out the expansion tank so thats probly the pissing head gasket? i think the thermostat might not be opening fully so not much water gets through to the engine then it overheats and has blown the headgasket what do you think? and also my chain keeps going very slack il tighten it up properly and then it goes loose again after a ride so i was wondering how you check if your chain is stretched? any help would be appreciated as im off the road now cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[finpos]

Hi Lee,

Shit Knackered old bikes, eh? Who'd have one

Definitely sounds like the head gasket has gone (again). Possibly due to overheating at some point, but on an old bike that can be down to a single completely failed component in the cooling system, or combination of absolutely everything not working as well as it did once.

The chian thing - make the distinction that chains don't stretch, they wear out. And there is no chance it would wear that quickly. I think it is more likely the spindle is moving for some reason (missing a spacer or washer so you can't ever tighten it enough?) Try marking where it is next time you adjust it, see if it moves.

Also, if the chain is old, it might have slack points and tight points along it's length. Make sure you don't adjust it at one of it's tight points.

perseverence....

finpos.

[lee125]

hi finpos thanks for the help could the thermostat be the problem? i might take it out and see if it will fix it cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[lee125]

oh and that chain thing could i put the bike on its centre stand start it up put it in 1st and see if the spindle turns? cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[kenny]

i know my chain when i had my nsr got slack after about 200miles if that because they stick cheap shitty chains on em so i replaced it with a did xring which solved that problem
____________________
KeNNy 100cc peugot speedfight 125cc Honda NSR125R 650cc suzuki SV650R 125cc suzuki GZ125 600cc yamaha YZF-R6

[lee125]

well iv done over 1000 miles on it in the last month and it didnt look new when i got the bike a month ago maybe i need a new one?
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[fuzz]

[finpos]

Could be the thermostat (by the way, the thermostat's job is to let water into the radiator when it gets hot). Could be worth checking.
But also expect a clogged up radiator. Unfortunately for you, the fact that it worked ok for a while (needle in middle of guage) suggests that the cooling system may have been ok, and the head gasket just failed on it's own.

By spindle moving, I mean forwards towards the engine, not rotating!

finpos.

[lee125]

so i should replace the chain? also the radiatior has a whole about 1cm high and wide you can see right threw it but its been sealed so it doesnt leak could this be causing it im going to take it to bits now and see whats happened should i blast the radiator threw with a power hose incase it is blocked or is there anouther way cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[kenny]

no dont do that ull nacker the radiator there really thin metal id just get a new one for it or one from the scrapper/ebay and replace the thermostat there only pounds for one
____________________
KeNNy 100cc peugot speedfight 125cc Honda NSR125R 650cc suzuki SV650R 125cc suzuki GZ125 600cc yamaha YZF-R6

[finpos]

I think we discussed your radiator before - the hole won't cause too much trouble. Don't worry about it. The fact that the radiator may be over 10 years old is more of a problem. Flushing it out would be a very good thing to try, but may not fix it.

So, by all means pull out the thermostat, flush the radiator and give it another go. But if your head gasket has gone, none of that is going to help you now.

You only really need to buy a new chain if you have adjusted the spindle all the way to the back of it's range of travel. Check first for tight spots in the chain, and that the spindle does not move from the position where you adjust it to.

Edit - just use a normal hose to flush the radiator.

finpos.

[lee125]

ok thanks i will do all that and the spindle is almot as far back as it can go about 1mm from the end cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[lee125]

took the head off and the gasket hasnt got a hole in it but on the inner circle bit where its meant to be black on the gasket has gone silver to the metal bit could this be causing the water to leak threw? cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[finpos]

Sorry, lee the answer to that is "possibly". Couldn't really say without seeing it.

Any marks on the head/barrel? you can normally see some discolouring if it's being blowing through.

finpos.

[Ichy]

[lee125]

ok thanks il upload a pic in a couple of mins
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[lee125]

heres the pics

the head gasket
https://img338.imageshack.us/img338/4148/dscf3206pg0.jpg

the cylinder head
https://img380.imageshack.us/img380/5351/dscf3205dx6.jpg
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[lee125]

anyone know what could have caused this? cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[lee125]

just tested the thermostat and it opens fully? cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[mr jamez]

That looks like it has had better days, is that some sort of sealer on there? Make sure you check the head is nice and level, I go across the width with a straight edge (steel rule) and look for any light appearing between the two surfaces. Make sure you clean the mating surfaces thoroughly with a soft plastic scraper. When you secure the nuts to the head studs do it in a criss-cross pattern gradually and use a torque wrench (23NM)
____________________
NSR 125F > BROS 400 > NC30 > BROS 400 > Trumpet S4 > '97 VFR 750

[lee125]

yeah its a liquid gasket thing im not going to use it this time though and before i fitted it all back together last time i skimmed the head and barrel so that it was flat and smooth and i tighten the bolts criss cross as you said cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[mr jamez]

The manual states that the thermostat should "open a minimum of 3.5mm when heated to 80C for 5 minutes"

It is probably the sealer that has caused you the problems, double check that it is all still level if it has been overheating.
____________________
NSR 125F > BROS 400 > NC30 > BROS 400 > Trumpet S4 > '97 VFR 750

[finpos]

Hmm, Liquid gasket may have been causing ALL of your problems!

Suggest putting it back together carefully with a new head gasket if you have cash to spare - looks like that one might not be too clever any more. Check it's all still flat as well.

finpos.

[lee125]

what should i do should i put a new head gasket on and put it all back together and see if it sorts it? also i have flushed teh radiator and tehres theres no blockages cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years

[lee125]

what could the liquid gasket stuff do to cause all my problems? cheers
____________________
cbt passed 01/07/2006 bike:92 dt 125 and 96 honda cr 250
theory:PASSED! A2 test:PASSED 08/11/2006 restricted to 33bhp for 2 years