Psto.. my new/second hand Lxr clone

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at a guess i would say they are the same as KLX 5.5 stem seals
i found some Viton seals the other night somewhere ?
will see if it's still in my history...

if you are thinking about a new TB piston, why not bore it and put in a 64mm ?
Classic Honda 50's Australia - TB Piston Kit - 64mm - Stock, Race Head and V2 Race Head [TBW0582]
do you have any machinist's near you that could bore your cylinder ?
if not my machinist can do it for around $50, but would also need the new piston to check clearances etc.
i have a spare ZS160 cylinder here that i could get done, then post it to you as a changeover
then when you get it, post your old cylinder back to me.
 
sleeves are cheap from akunar with pistons.. or a tb piston and a 67mm sleeve.

Asi i was explaining to stu stock bore there is not too much need for more power unless on a track.. some have had alot of hours on a 64mm kit though

The valves have the same amount of hours as the brand new pistons. Also had a tap ran through the rocker retainer and every other bolt hole i could get to.

Not sure why you want another bikes valves? these are good enough imo unless you wanted to go to titanium but even then whats the point you dont need the rpm that much..
 
I have been debating that, I might take you up on that when I get the cash up to buy whats needed. Trying to sell parts on fb is a nightmare, I put the x4r together as a roller with the pstos old forks and cant get 50 bucks for it, talk about stingy!! Hopefully in the nxt couple of weeks I can land another roofing contract, that would pull me out of the poo quite nicely ;)
 
Well I may have found solution to all this. Found a bloke with dhz 160 outlaw, willing to swap my sigma rally car for his bike, 250 his way. Considering I was selling he car for 200 bucks im pretty happy, missus not so much lol. Anyway engine will come out, and get all the tb gear. I was asking about valves to see if I could match up a set of stainless wiseco valves if ever I need to replace them. Ifthe valve stem seals where replaced when you rebuilt the engine, I shouldnt need to do them again should I? I reckon she hasnt liked not having a proper hone run over the bore, and the rings have just failed to seat in. And now its running a 14 rear I think the torque from a bbk could be usefull..
 
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Yeah I saw that thread, not sure why zac didn't just get it machined. I think I found the source of the gearbox issues, the bearing on the clutch shaft wa shot, around 4mm movement, which was alloing the dogs for second to slide across each other. The crank had more slop than I anticipated, zac had mentioned it wasnt the best, but I didnt think it would be as bad as it is. Not sure if I will even use the adjustable stator on the other engine, I dont have a timing light to set it properly anyway.
 
I cleaned the piston up as well today, and found a couple of nicks in the valve relief, inlet side. Hard to get a good pic, but it looks to me like the edge of the valve has caught it ever so lightly.
 
gottagetacheaperhobby said:
I cleaned the piston up as well today, and found a couple of nicks in the valve relief, inlet side. Hard to get a good pic, but it looks to me like the edge of the valve has caught it ever so lightly.
Click to expand...
There was a couple of nocks and stuff on that piston when it was new mainly from poor handling from shipping etc.. didnt have much of a choice because there were no other ones in store.. They were small handling niks only on the dome somehow..

they will not affect performance (other than maybe knock at worst case but not likely at all) The crank slop was acceptable just (china specs) but really any movement is a no no.. But considering the amount of room i had at tdc and the new cam chain i let it slide..

Pics of the clutch side? I only ever had the clutch side off, was going to replace the clutch pack and got stuck on the clutch nut and decided otherwise.

" Ifthe valve stem seals where replaced when you rebuilt the engine, I shouldnt need to do them again should I? I reckon she hasnt liked not having a proper hone run over the bore, and the rings have just failed to seat in. And now its running a 14 rear I think the torque from a bbk could be usefull.."
Not too sure about that one stu.. Id say heat plays a factor.. but once again i have had it running for quite some time with the pitsterpro se frame and that oil cooler so maybe rule that one out.
Did it blow smoke under acceleration? It could be the not honing of bore (my bad sorry) When funds are low funds are low..

With the valves TB have some stainless steel intake valves now the exhaust is stainless i believe i personally wouldnt go to any other than the original source of valves for price benefits and they are made in similar ways etc..

I do the valve stem seals because it take 15 minutes and peace of mind really i did it on the previous rebuild because i thought it was heat that caused it and i was right (scratched bore) And i believe the valve stem seals will fail before the rings. also means there would be no blow back pressure but smoking heavily.
 
I will get some pics tomorrow, the rubbers are definitely gone in the clutch, and the bearing behind it all was nice and sloppy to.
I did read that the tb valves were prone to cupping, that was the reason I was looking for other brand replacements, but if they fixed that issue I will stay with stock. Thinking of going for the alloy rockers and ti retainers while im at it, they claim the ti retainers are stronger than stock, but i remember you saying you had heard of them failing so a little undecided on the retainers. I would like to find someone to do a port job on the head, I was suprised to find the exhaust port only 23mm in diameter..
 
gottagetacheaperhobby said:
I will get some pics tomorrow, the rubbers are definitely gone in the clutch, and the bearing behind it all was nice and sloppy to.
I did read that the tb valves were prone to cupping, that was the reason I was looking for other brand replacements, but if they fixed that issue I will stay with stock. Thinking of going for the alloy rockers and ti retainers while im at it, they claim the ti retainers are stronger than stock, but i remember you saying you had heard of them failing so a little undecided on the retainers. I would like to find someone to do a port job on the head, I was suprised to find the exhaust port only 23mm in diameter..
Click to expand...

That's ok, the YX160 heads are only 21mm where the pipe bolts to(head on right)
Ported head on the left is now 24mm i/d

Akunar are cheap for Stainless valves etc.


 
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If retaining stock bore then i would say that the valves are already oversized..
Then the only gains would be had with less lift and different durations and lower airspeeds etc.

Remember takey use similar size valves too.. main diff they have a smaller stem and a skinnier golf balled cutdown section. 4.5mm stem.

I heard that they can crack due to the nature of the material.. and you do not know until it fails.. However the weight gains are amazing when held in your hand and the alloy rockers are much much lighter so i hear (However thats lesser of difference due to the weight is swinging off a pivot etc..

I haven read about the tb valves cupping.. maybe over many hours.. but by then they deserve new valves.. Was talking to terry from firepowerminis *aka minigod About the valves.. he can get some stainless valves but they are around $70 a peice so i remember.

I have heard the titanium retainers and alloy rockers in quite a few engines and wondered how that skimpy little wristpin/rod/piston/chinametal stays inside itself. (especially with 64mm kits) Sounds mad too

I don't know much about the new tb rockers,, haven't seen a review yet.. takeys may be a safer option.. for the moment.. Pretty sure they use needle roller bearings unlike the stock bushes (i think don't quote me)
 
my67xr said:
That's ok, the YX160 heads are only 21mm where the pipe bolts to(head on right)
Ported head on the left is now 24mm i/d

Akunar are cheap for Stainless valves etc.


Click to expand...
I will email akunar and see what his prices are, I will get a qoute on bbk and ss valves.


I dont want to go bigger in the valves zac, just get a exhaust port polish and the casting marks taken out, and some new stock sized ss valves installed. I dont have a valve spring compressor and I dont like my chances of getting the collets back in without one, and its damn fiddly trying to get in the exhaust port to sand the casting marks out. With the taki rollers, whats involved to change them over? I imagine they would be dearer than the 80 odd bucks for tb alloy rollers..
 
So fellas need some advice on the tb bbk. Is the long skirt piston useable on the zongers, or do I have no choice but to use the short skirt and lose some piston life..
 
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