Class A bike build help engine wanted
 

Hello

Been racing an 800 in minitwins the past couple of years (met a few of you DD guys along the way) .. and decided to give it a go.

I've got a '99 750 ie that i'd been using as a track bike and want to convert it into a DD bike.

has anyone got an engine to sell?

or does anyone know if I could just swap the barrels/heads

Any advice would be much apreciated :D

You can just change the barrels & pistons the crank is the same you would need to check the rods I'm not sure about those pretty sure the heads are ok.

I have a pair of barrels & pistons if your interested.

cheers PM me with the details of what you want for them

anyone know any different ..

Is the 620 5 or 6 gears .. the box on the 750 is 5

I'm guessing it would be easier to keep on the boil with the 6 speed??

Personel preferance.
I prefered the 5 speed as 6th gear never really got used. 6 speed are harder to come by.

The 620 heads - cams especially, like the 800, are better than the 750.
I have a 620 engine that I'm never going to use now if you are interested.
5speed, good condition, but I've never run it.
I'd like 500 for it, but am open to offers.

phil

The rules state you need to run standard 620 heads and Cams, the heads are Stamped with the coding 2S (or S2).
So it would be possible to fit heads and Barrels from a 620 to the 750SSie.

I ran my 620 on a 1.5M ECU for a year and Andy Challis did so last year winning the odd race along the way. Although the Rev limiter on them does come in a bit early compared to a 620s ECU

Many Thanks guys

Skidlids .. I take it the 1.5M ECU is off the 750 and the 620 is another variant (escuse my ignorance) .. and I take it the looms are the same??

The 750SS ie uses a 1.5M ECU, the 620 uses a 5.9 ECU
The 1.5m has a single multi pin connector where as the 5.9M ECU uses two connectors.
As standard the 620 ECU is coded to the Clocks with the Clocks in turn coded to the transponder in the key

As such the looms are very different, even the 750/900SSie had different looms, the earlier one had the fuse box on the fairing bracket the later ones had it next to the battery under the tank, which I have found a lot better for using as a race harness.

This throws another difference into the Mix. The earlier bikes use a A0 version of the 1.5M ECU where as the later bikes/harness uses the A8 version. Main differnce between the A0 and A8 versions of the 1.5M ECU is the way they are interlocked, so can't be swapped from early to late loom and vice versa.

Speaking of 750SSie's and as its sunny out I think I'll take mine for run over to H-Cafe and see who else is out on their bikes today

Should also mention the Injectors are different, both use 45mm throttle bodies but the 750 uses early type green injectors that flow 270cc/min where as the 620 uses the later Pico Brown Band injectors that flow 330cc/min.

Both use the same Throttle Position Switch and 3-Bar fuel pressure regulator.

Fitting a PC3 USB to either will allow you to fuel Map each cylinder independantly

Keep the info coming Skidlids. I have a 750ie setup for racing and am considering converting it into a 620 class A setup. Any suggestions would be SUPER helpful.