Forum

[Roeland]

Hi,

After 17 years without a bike I eventually bought the beginning of this year a new C5 EFI in military disguise. Since I covered about 6000kmm and added the free flow goldstar exhaust (with silencer – other ways way too loud) , front pipe, K&N air filter, power commander 5 and Dynojet Autotune module. On Monday I hope to take delivery of a 19 tooth sprocket and fit this too.

Further aspirations for upgrade include to gas flow the cylinder head, the EFI performance valves and the EFI big bore kit.
Has anybody fitted the later yet to the latest EFI engine? Could you give me any advice or feedback regarding the installation; performance gains, etc…?

I also would like to obtain some more information on the ideal AFR mixtures at the various rpm and throttle opening positions?

Regards

Roeland

[trevorch]

Hi Roeland,

I have a very standard B5, except now with an 18 tooth sprocket. Has covered 4,500 km. Second hand experience from my German deale,r he has done all that you mention, including 535 with 8.5:1. Not sure about special valves or gas flowing the head. I gave it a road test before I bought mine from him and the performance was quite a Wow. His other mod was a fantastic four cylinder front brake with a much larger disc. I think this sort of this is a must, if you intend to use the power for more speed. His previous bike was a tuned 612, but he says that his modified EFI is much better. I will do the 535, exhaust and Power Commander next year. Seems quite good value for money, ans also go up to 19t. Cheers Trevorch.

[Roeland]

Hi Tervorch,

Interesting that you mention the disk brake. I was advised that mine is quite wobbly and that I should replace it with something more substantial. I read on a couple of forums that the standard disk is often out of alignment. Could this be a design or manufacturing fault?

Kind Regards

Roeland
Cape Town
South Africa

[trevorch]

As in a previous post, I found my disc run out was 0.5mm. Workshop manual says max allowance is 0.3mm, so dealer agrees to supply a new one. The bigger disc he has with 4 cylinders, was Italian I think. First time I touched it, I nearly went over the tank. Found out 1 finger was enough, worth considering. I will post details when I next see him.
Cheers TrevorCH

[trevorch]

Hi Roeland,
I visited my German dealer today, to have a new front brake disc fitted under warranty. This dealer has built a "special" EFI based on the Classic. As mentioned, he has enlarged to a 535 fitting the special piston mentioned by our hosts, the Dyno Commander and sporty exhaust with the single wall downtube. He mentioned that it was not possible to fit larger exhaust valve, just not enough room for a larger diameter, so he just polished the inlet and exhaust ports. I will get the same modification after Xmas. I mentioned before that a bigger brake disc might be useful. To a standard 18 inch rim, he has fitted a Brembo 320mm floating disc and a new Brembo 4 cylinder caliper with 15mm diameter pistons. The fork ends look to be standard EFI with the caliper mounting on the existing bolts. Very strong braking. Cheers TrevorCH

[Alan R]

--------Blimey, mate !!!....... I bet that bends the spokes ?? Good stuff, Brembo. Always performed faultlessly on the Guzzi Cali 1100i

[Roeland]

Trevoch,

Thank you for your input. I´m now also planning to change the tires to Continetal TCK 80 or something similar. The standard rear tire on my bike is a 120/80 18 and the front a 90/90 19. Does anybody know if I could increase the sizes to 130/80 and 110/80 respectively?

Regards

Roeland

[guzzimeister]

Hi all

very interesting discussion. I've got a Classic and uppped the gearbox sprocket to 19T and found it improved the fuel economy slightly and was much more relaxed. I am toying with the idea of a Dynoject Power Commander having used one on my Guzzi V11 with very good results, and also beacuse at some point I ant to change the current chrome silancer to a stainless one.Having heard bout the 535, no tempted to do this too. Anyay, quick question: any idea what these mods do to the fuel economy? I'm getting between 80 and 90 at the moment, and while it would be nice to have a quicker bike, I don't want to do this and get 50mpg. Might as well stick with the Guzz in that event. As my mate says "if you want a bucket don't start off with a pineapple". Seriously though, any mpg indicators for these mods?
Cheers
Guzz

[Roeland]

Hi,

I cannot determine my fuel consumption yet, but all indications are that on the non European version (without the lamda sensor and with a PAV system) the consumption will be dratically lower. Since I blocked the PAV system and installed the autotuner the AFR is reducing dramatically. To get to a mixture of 13:1 at idle I had to change the 0% throttle position to about 20% less fuel than the standard ECU was delivering and all over the range - except for very hard accelleration - the autotuner provides less fuel for a smoother and more powerfull ride. I guess that European models are tuned very lean in comparrison with the non-European models. Before any modifications I used to get about 25 to 35 km per liter depended on speed, pillion and luggage.Going forward I expect a fast improvement on this.

PS. I now also fitted the 19 teeth sprocket and agree that it defenitely provides for a smoother ride. The gears are also more purposefull.

Regards

Roeland

[Maturin]

Thanks Roeland and trevorch for sharing your experiences. I travelled 20´kms with my G5 and plan to have a l closer look into the head next winter. Some upgrades concerning a bit more top end would suit me well, so please keep on posting.
@trevorch: isn´t the brake upgrade to a Brembo caliper and floating disc totally overkill? After I fitted Hitchcock´s steel brake line I´m able to do stoppies with my standard brake. So I think the limiting factor is now the tyre and not the brake power.
@Roeland: Unfortunately the tiny Bullet rims allready hit the wall concerning tyre size. Looks like the standard size is the biggste possible, when oversizing you´ll squeeze the thread and probably ruin any performance gains. But with the C5 you can use the Bridgestone BT45, and I can also recommend the Heidenaus I´m just using: K34 looks nice and sticks very well, when inclined the limiting factor is not the tyre, but the foot peg. Cheers Maturin