TZR 125 - Derestricting - HELP!!!

[FingerZ!]

Fellow Bikers

I have an F-reg TZR 125 and I need to find out:

1) how it is restricted,
2) How to derestric it!

Also think the lump needs rebuilding cos the power band seems to be narrow and all over the place unlike on teh reviews i have read for this bike. Not even enough power to keep me going along at low revs just below power band - strange!

Help would be greatly appreciated!

[djbadger]

As far as derestriction goes, i have only ever dealt with it third hand (as in not done it myself) but:

From what I have heard about re-striction kits, they are simply washers (for want of a better name) that restrict the flow either from the manifold to the exhaust and/or from the carb to the manifold.

If you take off your exhaust, do you see a circular plate that sits in the end of the exhaust or in the manifold? if so, remove it or drill it out a little.

I think thats it, but that is for bikes that have to be restricted by the owner after sale as opposed to those bikes that are factory restricted.

:?:

[FingerZ!]

Yeah I heard bout the washers too - havent noticed any as yet but then i havent really messed with the engine too much yet - was too eager to get the frame done n get the engine back in as it worked enuff already

Aparently im meant to have a servo to control my powervalve but i think thats on the later models like dans - chop a black wire and it goes from 12 BHP to about 25+ i think

if only it was that easy..... :roll:

[djbadger]

Hmmm

When Simon had his TZR250 he had servo-controlled gubbins. That thing was a rocket ship.

So, what year is your TZR then? Was there an earlier model that didnt have the servo control? :?:



PS.
Where are these piggin' photos already. I wanna see this thing while its still in one piece! before all the engine work begins! :lol:

[FingerZ!]

Yeah the TZR125 of dans is pretty quick - rode it up a slightly twisty road near him and without realising i was doing 60!!! the nuts m8! had plenty more and that was only a 125 version so i bet the 250's are not shy of a bit of speed as far as little engines go!! :D

AS for the pics of my bike, will try my best to get to dans when he is free this weekend and get some shots before it goes to bits in the daylight - normally i dont get chance to get up there before its dark unfortuately.

Hopefulyl when we take the head off there will be something stupidly simple wrong with it like a carbon'd up power valve and exhaust port and so we will be able to temporarily bung the head back on and get some running out of it! :D:D:D

[FingerZ!]

oh yeah the bike i have is an F-reg - dosent have the servo

[FUBAR]

Ello m8 its a very simple to derestrict ur bike uve basicly got 2 options ...
before ur bike will do 100mph first one is buy the YPVS kit which basicly comprises of the electronic servo motor which rotates the valve via cables and a pully system... (160 quid at a shop OMFG) or 45 quid at a brakers..
Or u can slightly modify the stopper plate that hold's ur power valve in the full closed position ... to hold it in its full open position .. :) ill post some pictures of how to do it soon ... or i can send u one i did earlier heheheh
u wouldnt believe how many of these ive got :S ive even got the electric bits and pieces but i carnt sell them atm because im thinking about building a little throw around bike for the winter ... DTR or a TZRR not sure yet ...
anyway ill send u some pics of how to do it or i can send u them ethier way ill post u some pics ... if ud have told Dan i could have sent u one with the other bits i sent u :S ... im sending Dan a reed valve soon and an oil pump so ill drop one in ..unless uve already got it sust??

l8r

[FingerZ!]

Hello mate!

cheers for the info - have already worked out how to lock the exhaust valve in teh open position even tho i was told not to do this - however i cant see that opening a port up to its full capacity would fook me engine!

anyways - it hasnt made any difference cos i think i need new rings basically - it misses and 'pinks' under load - wont pull third gear up wards yet revs out as much as it can in 1st and second - it only maxes out at around 8.5k tho so i know sumthin is up - think i have piston slap also

i rekon it just needs a rebuild - top end at least - dont really wanna go mad on it, just get it running properly.

when i rode it to dans the first time, it was really ruff and difficult to get any revs out of it - was running killer lean so when it revved it went but only up to 8k for sum reason. then i managed to get it up to 60mph where it held for a few seconds, spluttered, and never went past 35 on the flat again!

cheers for the offer of the bits m8 - will let you know unless you have a fully working engine lol! - you have reminded me also that i owe dan about 50 quid for the bits still!

must pay him!

:roll:

[Dan]

<cough> 55 ;) No rush mate - I've got to get my engine rebuilt by the yammy dealer... im taking it up there thismorning for them to have a look at. Jay reckons it may be about to seize, so im well not impressed - Still, at the end of it, i'll have kick arse power!

[FingerZ!]

55 lol - ok mate i will draw the wedge out later before i forget yet again!

cheers for that m8 - feel a bastard for lettin it go so long!

its an arse bout your bike, but hey it will be the nuts again! - get them to overbore it whilst its being rebuilt!??!

[ScrewyLouis]

i have a g plate tzr and am experiencing the same problem as fingerz, altough power is smooth, absolutely bugger all power over 8500 revs, i have heard of the servo kit, does anyone know of any suppliers? otherwise any knowlegde of opening the power valve manually would be greatly appreciated as a mate has just bought a mito and needs some competition.
also would anyone know where to ind a replacement kickstart?
cheers

[Yamaha]

Ello m8 its a very simple to derestrict ur bike uve basicly got 2 options ...
before ur bike will do 100mph first one is buy the YPVS kit which basicly comprises of the electronic servo motor which rotates the valve via cables and a pully system... (160 quid at a shop OMFG) or 45 quid at a brakers..
Or u can slightly modify the stopper plate that hold's ur power valve in the full closed position ... to hold it in its full open position .. ill post some pictures of how to do it soon ... or i can send u one i did earlier heheheh
u wouldnt believe how many of these ive got :S ive even got the electric bits and pieces but i carnt sell them atm because im thinking about building a little throw around bike for the winter ... DTR or a TZRR not sure yet ...
anyway ill send u some pics of how to do it or i can send u them ethier way ill post u some pics ... if ud have told Dan i could have sent u one with the other bits i sent u :S ... im sending Dan a reed valve soon and an oil pump so ill drop one in ..unless uve already got it sust??

l8r
Hello mate!

cheers for the info - have already worked out how to lock the exhaust valve in teh open position even tho i was told not to do this - however i cant see that opening a port up to its full capacity would fook me engine!

anyways - it hasnt made any difference cos i think i need new rings basically - it misses and 'pinks' under load - wont pull third gear up wards yet revs out as much as it can in 1st and second - it only maxes out at around 8.5k tho so i know sumthin is up - think i have piston slap also

i rekon it just needs a rebuild - top end at least - dont really wanna go mad on it, just get it running properly.

when i rode it to dans the first time, it was really ruff and difficult to get any revs out of it - was running killer lean so when it revved it went but only up to 8k for sum reason. then i managed to get it up to 60mph where it held for a few seconds, spluttered, and never went past 35 on the flat again!

cheers for the offer of the bits m8 - will let you know unless you have a fully working engine lol! - you have reminded me also that i owe dan about 50 quid for the bits still!

must pay him!




can i have the infor too...as my valve is also struck

[FingerZ!]

Hello chaps - tis ok thanks i have derestricted the bike - my god did it fly when it ran properly for a full 30 miles lol! :lol:

I took the pegged stopper plate out and basically stuck my finger up the exhaust port to make sure that the valve was fully open and then held it there whilst i nipped the bolt up on the side! - hey presto! i dunno what the problem is when people say that this is an 'attempt' at de restricting - i can think of plenty of bikes that dont have a restricted exhaust port and if pening the port were to cause lots of problems then it wouldnt have been designed so that you could servo control or just manually open it woul dit?!?!

:)

[Dan]

and the best part of it all is when its taken out, you can see right through to the other side!!!! .... ok... i'll shut up :D

Oooo.... Tim has a top of the range kickstart he might sell to you :lol: If not, try a breaker or your local Dealer.... they shouldnt be to expensive.

[ScrewyLouis]

many thanks. shall have a ganders tommorow. any iidea what kind of speed you can get with the valve open & where it redlines :?: ive had a lot of crap from the engine i.e numerous seizures, 3 rebores and a big end rebuild. really dont want to blow it up tryin 2 go too fast :lol:
cheers
louis

[Dan]

Has it seized since its last rebuild? .... and what caused the seizes, do you know?

D.

[FingerZ!]

LOL @ Dan!!

I just realised what you meant when you said bout seein through the power valve! - the bit on the video innit! - another timbo schmuck moment on the camera eh!?

:lol:

Yeah kick start is quality altho i refuse to get one until the bike is running properly!!!

Once the valve is open you can rev almost off the clock in the low gears - mine ran right for about 30 miles and it was pulling strong as you like even at 65MPH - ran out of road lol! couldnt ride it too far out you see as i was worried bout the bike giving up and having to walk it home uninsured, un taxed, un licenced LOL!

altho if you say your engine has been siezed a few times i woul dstrip it and do a propper rebuild - make sure the big and little end bearings are ok and that the piston is a good fit and there is no piston slap etc - make sure that the oil pump is turned up nicely - remember, a lot of oil is smokey but **** it run it with plenty and adjust it down slowly!! nothing like lack of oil to **** your engine up - not to mention a weak/lean mixture - that is common causes of ceasure.

[ScrewyLouis]

i reckon it was the oil pump the first time, the little retaining washer/ bolt on the throttle cable had slipped down while i was bringing the bike home in a van, and me in my biking infancy didnt realise. then after that i had no idea why it seized the next couple of times. i have turned the pump right up whilst running it in tho, only to have my kickstart snap and fly across the road after turinig it down.:x but so far apart from a couple of smokey starts, no problems.
lou