Light Weight Flywheel ??
 

Reading about light weight flywheels and the like.

Has anyone fitted one to a 748S ?

If so what difference did it make ?

I fitted a light weight clutch basket and the engine spins up much faster I am assuming a similar improvement can be expected;)

But I've been wrong before:bouncy:

If you are watching the BRNO Moto GP we are the eleven on the front row of start finish with the James Ellison T shirts spelling GO ELLISON 77

Hoping for a good weekend (60p a pint):sing::sing::sing:

I'm sure Nelly had one fitted on his 748, it's something I've been considering for my 996. He'll do you a good deal on one I'm sure aswell.

I've got one fitted to my 996. I haven't noticed any loss in engine braking but what I have noticed is that it spins up a lot quicker. Put some shorter gearing on yours as well and it becomes a lot more entertaining!

:D

Great upgrade, really makes the most of the revvy 748 motor!

The alloy flywheel is about 800g lighter than standard, so even more weight saving than the light clutch and right on the end of the crank!

feels a bit like a lower gear, but unlike lower gearing, doesnt run out of revs faster.

Word of warning: get it fitted properly, note the type of locktite to use and the torque settings. well worth re-torqueing (not sure about spelling) at each service. If it comes loose it destroys itself and takes the main bearings, and maybe the bottom end shells with it.
if you are not spanner happy, then pay an engine builder, who has done it before, to do it, it will cost about 3 hours labour, some 3bond and oil/filter. but if it comes loose you get full comeback.

a cheap and fun performance mod.

[Edited on 25-8-2005 by wilf]

I have one for sale!!!!
 

Is it the same for 748 916 996 if so how much? :)

it was on a 748 with an 853 conversion . . .
 

not certain if it will fit a 9**

£50 incl postage and its yours!

Khushy

I will find out and if it fitts I will have it.

There are three types of flywheel on the 748-9**'s.

The early 350W alternator bikes, which I think Khushys flywheel will suit, have two yellow cables coming from the alternator.
The later 550W units have three wires and use a different flywheel.
The last ones are the SPS flywheels. These bikes use the P7/P8 ECU's and have two flywheel pickups on the LHS cover.

1999 is the approximate year for the change between the first two, but you can get 350W bikes registered late.... ;)

After the cans, it was the next mod I did to my 748. It was also a must have in my new engine to. Love it. Spins up quicker and improves engine braking slightly. Great mod!!

Agree with Nelly (well, how could I not). One thing the lighter flywheels will highlight is if the fueling setup is less than ideal. That is, the larger mass of the standard flywheel can mask marginal FI setup. It might be a good idea to have the FI checked and setup at the same time you fit the new flywheel.

Its possible to take it off completely.

I've fitted a lightened flywheel to my 98 748 and it does make difference the engine rev's a lot easier now and it does feel faster, however starting it and getting it to tick over when it's cold is a pain, but I found just slightly increasing the tick over rpm has helped but once its warn its fine.

the bikes with the early type fly wheels (two yellow wires) can be used with no fly wheel at all which is why some people have them for sell.

ive just had my bike converted to a 853 and whilst cjs performance were doing the upgrade they completely removed the flywheel andn it does seem to make a difference although having a new engine amy be something to do with that

will report back after silverstone to add my full findings, its going to be fun

How does having no flywheel affect the charging system, and doesn't the engine feel more lumpy without it?

Excellent reading, I think when my bikes run in I might remove it as I have always had major problems with wheel hop on the corner entry. The only bikes I havn't had problems with were the 2 Strokes I started off on.
I always run high tickover on all my bikes about 1500-1700 rpm.

it wont stop wheel hop.
that's due to engine braking hence why your 2 stroke didn't do it.
if you want to get rid of that you need a slipper clutch. or don't change down so many gears before the corner

agree with the slipper clutch comment, that will be my next addition.

the bike runs fine without the flywheel, spins up lovely but probably not a goood idea if you value tyre life, i was actually spinning the rear up a couple of times at silverstone, great fun though

Red Racing Parts sell the Ferracci flywheels - very nice on my 996

http://www.redracingparts.com/en/english.htm

does this apply to an sps too - or do they have lightened one already?

They don't seem to have one for the SPS - I seem to recall being told that the SPS already had a lightweight flywheel and that adding one to my 996S engine would give it identical specs (apart from the injection and sensors). Could be wrong tho' - someone with more knowledge needed here.

SPS has a steel flywheel as standard.

It has a different one to the S as the SPS uses twin pickups for the P8 ECU, and S uses single pick ups for the 1.6M.

the SPS flywheel may be slightly lighter, but not by much and its simply because of its design, rather than designed to be lighter, if you know what i meen.?

There is a Ferrachi flywheel for the SPS with 4 steel inserts as pickups but the last time i ordered one it took ages to arrive (not much demand to make them i guess)