Standard cylinder heads; much difference?

[bruce moore]

Andy,not knocking anyone,ive never run fuel injection,never had the money or chance,yes i appreciate motec is good for data logging,what i cant understand is why a standard engine cant run reliably with a standard ignition and loom ?,surely this in the long term would bring costs down and make the class more competitive.regards mate

[teamradar]

Bruce, Even the standard carbs on your old ZZR had to be jetted to get it to run properly.
You can't change airboxes and exhausts that much and expect things to run properly without some adjustment.
A standard ecu with power commander is as dear as a kit ecu & a kit ecu with a seperate logger is probably as much as a DTA or similar. You can't just buy new jets anymore.There are enough options out there to fit most budgets.

[bruce moore]

your right Andy,suppose the days of a trip to the dyno to set up for the season are gone .never messed much with jetting,just used to move the needle !

[idris]

I'm like you Bruce but I am "afraid" to say that things have moved on & maybe we have'nt.
It doesn't help when I ride a BSA.......

[realroadracer]

Rubbish. The recent disqualifications of McAdoo Kawasaki and TAS Suzuki in the Supersport 600 class seem to be forgotten. If you cheat and your caught you are out no matter who you are.

Paul Phillips
TT & Motorsport Development Manager

"If you cheat and you're caught you are out no matter who you are".

Mods, should this be another thread? I'm trying to find out what effect COMPLIANCE with the new regs had on people's TT experience. Cheating, alleged or otherwise, is a different matter. Or is it?

[flexford]

Mods, should this be another thread? I'm trying to find out what effect COMPLIANCE with the new regs had on people's TT experience. Cheating, alleged or otherwise, is a different matter. Or is it?

*Edited after Geoff B's corrections*

Mods you better scrutinise this reply as well because I am going to be treading on some dodgy teritory

Geoff, just to tie your original topic of this thread, in with other tangents some comments below:

Re modifications below the head: there are two obvious ways to go when we talk about modifocations below the head - HC pistons and/or work to the crank. This year I believe at least two teams went down the line of HC pistons. The one problem that seems to be coming to light with HC pistons is the fact that the valve springs in a homologated head may not have the valve clearance to handle the HC piston

Now in to super dodgy teritory: A comment was made at the TT that two teams ran a particular configuration of HC pistons in their engines. The make, year and model of the engines were the same and the two sets of engines were built by the same tuner. However the "rumour" was that one team ran standard valve springs and the other team ran kit valve springs. The team that ran standard springs dropped a number of valves in a number of different engines and thus limited their time out on circuit. The team that was rumoured to have run kit valve springs didn't drop one valve and had no engine issues.

So in a nutshell, the modifcations carried out below the headgasket have to be managed very very carefully otherwise your homologated cylinder head will not cope with the modifications made below the headgasket.

Re Motec: although the Sulby speed trap is a bad measure of straight line bike performance I think if you marked who was running Motec and who wasn't the weighting would be towards the top 50% ... that could because the fuelling is closer to ideal or only the top runners use Motec ... one has to make their own mind on that point?


To everybody reading, I don't want a written slap for using "rumour" etc, but I don't want huge legal suit slapped on my arse ... I am sure people can read the missing parts

Best wishes


Kelly

[steve-e]

all good fun

[matthewsayle]

yeah all good fun

didnt I just say earlier this thread was started for rumours and slating.

Its obvious standard engines is not and more reliable or cheaper cos everyones going motec or spending a fortune on the bottom end etc etc. Anyone got any ideas how to make it cheaper c'mon theres a recession

[realroadracer]

yeah all good fun

didnt I just say earlier this thread was started for rumours and slating.

Er, no Matt, I didn't start it for that reason.

Ok, I give in.

[steve-e]

Don't give up Geoff we are getting some interesting responses in there.
It seems to have not made a lot of difference to top speed, don't know if it's made any difference to mid range and reliability on sidecars seems generally to be down to oil systems and ECU stuff more than headwork.
As a summary so far, does that work?

[oldbelly]

Kelly extra compression isnt the problem. Its the piston hitting the valve thats the problem . This kit homologation / standard road bike homologation needs to be clarified to the letter. The way I read it only standard road bike parts are eligible. Was this the case ???

[Alan Richardson]

Great post by Kelly!! Gets me thinking, regardless of how high profile the team is, why wont someone just say....standard is standard. As in, everything barring sump, etc needed to run in a sidecar. For gods sake, its not rocket science is it! Whats wrong with EVERYONE running standard motors??? ( i shall wait to be shot down ) Come on then....whats wrong with it?

[kew]

Standard sound like a very good idea but:

Even new engines off the assembly line can vary in power by 10+ bhp

My 06 Honda is not as powerful as a later Honda so I would need to have my chassis altered to fit a later engine, more expense.

One manufacturer always has a more powerful engine than the others in any given period, the logical conclusion to having standard engines would therefore be a one make class.

[steve-e]

One manufacturers engine tuned will make more than another manufacturers, they won't be identical but it's not a one make series now?

[Alan Richardson]

Keith, i understand all that but it still dosent answer the question. Why not standard, for everyone. If the bhp figures vary, then so be it. I understand people wont want to spend loads to change motors for 10bhp, but surely you have to start somewhere.