Buggery Bollox b*****d

[veg]

That is all.

[midlifecrisisrd]

Oh, oh

What's happened

Steve

[veg]

Tz top end not such a cracking idea with tz race pipes my dreams of pissing all over you pv jockeys appear to be just that dreams.

[Yogi]

Come over from the dark side

[midlifecrisisrd]

That's a right p1sser mate, must be gutted

Would Dave's pipes move the power much lower down the revs?

Or would it still be narrow?

Instead of a total loss and changing to ypvs could you not do some damage limitation and just use an LC top end?

Steve

[dusty350]

Trubrit has done the Tz top end - what set up does he use - pipes wise ? As the bike is already with Guru Dave, I would see what he can come up with. If anyone can sort it, Mutts is yer man !

Dusty

[4l04ever]

TZ700 porting is very close to LC porting, so must be the pipes causing the power characteristics. You could look at modifying the original TZ pipes. They would need to be made longer to get the revs down.

[veg]

Thanks rob
I have said to Dave I will probably put miles on it then get him to make some pipes. He said exactly that that the tz pipes are too short. It is all top end at 9000 plus rpm which will be unrideable been great when I was 18 not so good at 49.

[veg]

Dusty, Dave has said it needs miles it’s really a smaller set back and a 1st world problem but I’m desperate to get some miles on it. Knowing what I know now would I have bothered nope I would have gone pv (yes Steve and Matt you heard it) or even big bore . Is it unique yep is there a reason for that probably has the motor alone cost me more than a decent big bore motor yep.
Live and learn.

[4l04ever]

I just double checked the default port maps. Top of exhaust is higher than I remember on the TZ750 port map. 26.5mm from top. LC is only 30mm. Higher the exhaust port, higher the revs for peak power :-(

Maybe speak to Kenny (TSA) to see if he can design some exhausts to bring it down.

One other option is to put liners in the TZ cylinder block and have them ported to match LC. This is what I was planning to do with my TZ so it looks like a TZ, but rides line an LC.

[4l04ever]

Tz750 map

[4l04ever]

LC port map

[veg]

Do you have a 700 one rob as Dave needs one for the pipes. Or can you point me in the direction of where I can get one? Cheers

[Yogi]

Gutted for you mate but I’m sure you’ll get it sorted

Sounds like pipes are the way to go so it’s not all lost

Matt

[4l04ever]

Not got one, so would need to get a cylinder measured up. The cylinder I have is a modified TZ750 one.

[4l04ever]

If you could have skimmed 2mm of the bottom of your cylinders and reprofiled the head, that could have worked, but would be nearly impossible to do on monoblock type cylinders :-(

[oldelsieboy]

Mar 14, 2019 22:46:06 GMT 1 veg said:

Do you have a 700 one rob as Dave needs one for the pipes. Or can you point me in the direction of where I can get one? Cheers

Tim, AFAIK the 700 & 750 port maps are the same, the only difference is the bore size, 64mm - 66.4mm

OEB

[midlifecrisisrd]

Would a stroker crank and a modified head help

Would that not help with the high exhaust port

Either that are skim the cases, not the barrel

Steve

[4l04ever]

Looks like someone else has put liners in a TZ700/750 cylinder...

www.ebay.co.uk/itm/YAMAHA-TZ-750-cylinders-and-head-with-Fahron-steel-liners-/233143576014

[oldelsieboy]

Mar 14, 2019 23:15:19 GMT 1 4l04ever said:

Looks like someone else has put liners in a TZ700/750 cylinder...

www.ebay.co.uk/itm/YAMAHA-TZ-750-cylinders-and-head-with-Fahron-steel-liners-/233143576014

Yup.



OEB

[4l04ever]

Mar 14, 2019 23:09:36 GMT 1 midlifecrisisrd said:

Would a stroker crank and a modified head help

Would that not help with the high exhaust port

Either that are skim the cases, not the barrel

Steve

Norbo has some 4mm stroker cranks for LCs in the pipeline... that could work too, and gain power...

[Tobyjugs]

Those ports maps make a lot of difference to the performance Rob. I would go the +4 route. You might even be able to use the TZ set up with the head modified to suit.

Powervalves PAAHH!!!

[veg]

Chaps thanks for all the advice guidance and support. I was a bit disappointed. That’s all it’s a real first world problem and I am thankful for everything else that I have. I am going to persevere with this I have too much invested to just give up and walk away and will get some miles on it then back to Dave’s for pipes.
Cheers again for all the help and messages.

[headcoats]

Did you get a dynograph of it

[veg]

Nope it’s coming in with such force the new clutch is slipping and as Dave said he doesn’t really want to start spinning up a new crank rings and nickasil liners without any miles in them

[muttsnuts]

yeah, its very peaky, just fixing the clutch this morning and then map and fuel the bottom end to allow some miles to be put on it

Its not all bad, just flat low down, the very short TZ pipes are fine for big BP high up, but they are designed for the very high exhaust port (Rob is correct at 26.5), once Tim has got a few miles on the new engine it will come back and I'll design some new pipes for it, might even graft a set of mid range LC pipes on to see how it goes with them before spending time and money designing a new set, they should bring the rpm and power back down

If it was a track bike and Tim didn't care about swapping the crank out a few times a year then it would be great, but peak power looks to be set to come in around 10500rpm or higher, which is not really much use on the road in this day and age

I can sort it, just down to what Tim wants from it, it should do good power with the right set of pipes on it

[midlifecrisisrd]

I was going to suggest bridging a set of "normal" spannies on to see how it runs even if just to put the miles on

Dave already on it though 😉

Steve

[veg]

That’s why Dave’s the man he knows his shite.