Tank Slap - Motorcycle Forum

Thought i would start up a thread here as it looks likely ( assuming we can agree a price) that i will add the 853 motor to my 748 and get it ready for track use but also so i can ride it there. Really enjoyed yesterday on track and whilst the bike is fine as is it does lack a bit of power and the current motor has done 24k miles without any major work.

The 853 engine has been built by Jeff Green who ran Gtec in Leicestershire. Basic spec is 748 motor bored to 853 cc.

It's got sps cams, relapped valves, ported and gas flowed heads, new gaskets though out, new crank bearings and shells, lightened and balanced crank, titanium pankle rods, pistal 853 pistons, machined combustion chambers, had a few new rockers, fully blue printed. Oil connector fitted for oil cooler, engine will come with the ecu with correct chip from cjs racing(Chris mapped it), race wire loom and also 916 throttle bodies as there bigger than the 748 ones. Ran 119.8 bhp on the dyno with 58 torques.

I would need to add a slipper clutch and might fit some Brembo P4 calipers as they can be bought fairly cheaply but i think theses were fitted to R models of that era so will give a bit more braking power. Would also need to change the fairing as the current one is pretty much mint and don't want that sliding the road. I think you can get sliders that fit under the fairings for 916 bikes.

All this will happen over next winter.

Looking forward to seeing the project unfold. Definitely take off the road fairings and put on some track or cheap ones. I would also maybe try and find a cheap scratched petrol tank. They're vulnerable and expensive/hard to replace! Carbon tank protectors didn't save mine.
If you're going to track it I would also seriously consider a trailer. Single bike Erde trailers come up on ebay quite often for £200 or so. They're light enough to be stored on their side in a garage out the way. I borrowed one of a neighbour and they're really good! If you're not riding to the track you can take spares, tools, clothes, tea making facilities etc. You don't have to worry about getting home should the worst happen and riding home after a trackday can be quite hard work anyway! My opinion is that a trailer can take a lot of the stresses out of a trackday!

You know it makes sense.

There is actually a tank on ebay that could be perfect:
http://pages.ebay.com/link/?nav=item.vi ... 68&alt=web" onclick="window.open(this.href);return false;

Will be a total weapon on track that Duke.

Look forward to watching this project evolve

Would you get more bang for your buck going down the 999/1098/1198 engine transplant road? Or is the intent to keep it as original as possible, hence just a reworked 748?

Mate at work just put a SBK spec 999 in his 749, turned it into a total weapon he reckons.

They are not a straight swap into a 916/748 frame, kiwi.

This engine is likely to be cheaper and better than a 1098/1198 s/h engine. it was only built early part of last year. It would need different looms etc with a different engine.

duke63 wrote:They are not a straight swap into a 916/748 frame, kiwi.

This engine is likely to be cheaper and better than a 1098/1198 s/h engine. it was only built early part of last year. It would need different looms etc with a different engine.

Yeah just talked to the guy at work about it, he mentioned even though they bolt in OK you have to faff about with airboxes, throttle bodies, looms, ecu's etc.. sound like you are on the right track then!

That motor sounds amazing don't under estimate how good those lightened engine internals will feel It will spin up lovely
The ti pankle rods will make a big difference

The P4's were on the 998's as well i think there pretty cheap second hand and are a good upgrade i did this on my 996. The motor sounds good and the 853 was plenty quick enough according to Neil.

Put an offer in for the engine which has been accepted so need to arrange a time to go and check it out and pick it up.

Is this the tuned one?

That's the one.

Nice

Was about to post, just do it but I'm too late!

SWEET

I've only just seen this thread.
This sounds like an awesome project Duke, although your 748 is almost too nice to be a track tool IMHO mate.

Is it worth dynoing the current setup then when you've fitted the new one dynoing the new one?

Whatever it will be a sweet bike.

Will you keep the old engine?

Had a long chat at JHP yesterday, Seems i need an oil cooler for track use so its added to the list.

Also asked about slipper clutch recommendations and was told STM is the best one to go for. They do a 48 teeth version which has some advantages but for what i'm using it for it seems the standard STM would be better.

C00kiemonster wrote:Is it worth dynoing the current setup then when you've fitted the new one dynoing the new one?

Whatever it will be a sweet bike.

Will you keep the old engine?

I know the current engine wont make more than 90 bhp so not worth a dyno. I'm planning to keep it for now but will see how the usage goes next year and then make a decision.

duke63 wrote:..... was told STM is the best ....

Surely that was a given..
StM.