siebenrock 1000cc kits

[cookie]

anyone got any experience of the siebenrock piston/barrel kits for the 980cc paralevers.

lightweight pistons, compression increase, any good?

 

[Kenny]

Cookie, about ten years ago I fitted a pair of R100RS barrels/pistons etc and there was a 'tremendous' increase in power...so when I bought my recent g/s..it already had the siebenrock kit fitted. Definately not as rapid as fiting the RS barrels etc..but there is no 'rocking' from side to side that I got with the RS barrels. Still feels as smooth as an 800 so that can't be bad. They've GOT to be an improvement over the standard pistons/power etc..but I havn't ( memory fade - age - etc etc ) ridden another standard g/s lately to compare it with.

Cheers Kenny

PS You should be in bed at this time !!!

 

[cookie]

i guess the RS pistons are higher comp than GS?

i'll have to look it up. i know siebenrock are 9.5-1

ps. you're right, i should be in bed

 

[Rob Farmer]

I swapped bikes with Migsel at the Hogroast, his is fitted with a Siebenrock kit while mine is a standard 800, there wasn't a huge difference in overall performance but Migsels felt more willing in all the gears because of the extra torgue. Worth fitting for the that alone I reckon.

I'm not sure you would notice that much difference if your bikes already a 1000cc though but you could put the 1040 kit on

 

[MATKAT]

Another way

My airhead has the siebenrock... and it does make it loads more torquey and extra grunt with the extra cc's. Can't see many other 80G/S's getting 114mph on the garmin either
My old 100GS had a conversion done by Andrew Sexton. He gasflowed the heads lightened the connecting pin from the piston to crank (which sieberock do) . Performance wise there was nothing in it, given the extra weight
You might find a better plan to just have the current set up modded by him, cost less too. Result the same as really all the siebenrock does is lightenthe pin and give you similar capacity on the 100.

 

[TERRY RYAN]

I have been told (how ture I dont know)???????
that with the siebenrock conversion kit
The Bikewill not run to well with Shit Fuel

if you want to use the bike for RTW

 

[cookie]

I have been told (how ture I dont know)???????
that with the siebenrock conversion kit
The Bikewill not run to well with Shit Fuel

if you want to use the bike for RTW

with higher comp 9.5/1 as opposed to 8.5/1 standard, that would make sense.

 

[Rob Farmer]

my 81 RT has 9:5/1 compression. It's rated at 70BHP. with the number of cheap airheads around it would be easier to swap the whole engine.

 

[cookie]

i really must try doing something the easy way sometime

 

[Garry H]

I fitted a siebenrock to my r80g/s....It went a fair bit better BUT the engine was far beyond the chassis....Even with some brake and suspension mods it was overpowed...I then got a r80gs basic that has the 100gs brakes forks frame and rear suspension....I removed the siebenrock kit and fitted it to that...Now that was a worthwhile mod faster without the flexiframe handling of the monolever ...I recon the old monolevers are best left at 800cc unless they well modified ( frame stiffened )...As for the compression and pinking the higher compression is a problem with crap fuel

 

[MATKAT]

Works well

In fairness i do have Ohlins suspension and billet brakes, and although i have progressive front springs the front is still a bit soft. However, even before theses mod's the siebenrock conversion was very useful, and as i don't use brakes much anyway felt the extra grin factor was well worth it. . The bike performs quite well on the twisites, but then I suppose i do just bimble along
The extra grunt provided when two up and with all the gear on is well worth the conversion, but it does not handle as well 2 up and loaded. Solo it's fine and works very well off road.
I have had no issues with fuel, just run unleaded with castrol additive. I have done 4000 plus miles with this conversion now. As far as i'm concerned a huge improvement over the standard 800 particualrly the mid range and the extra grunt is marked

 

[JohnnyBoxer]

Mine seems ok, but i know no better

Saw 90mph with it, but with zero screen, that was all my neck/head could take.
My frame has HPN strengthening mods and it all felt taut, but as Gary says it might too much for a standard bike

 

[Gecko]

MiGSel recently fitted the kit to his R80 g/s - bloddy thing goes like shit off a shovel now. He likes it ....a lot !!

 

[MATKAT]

Exactly

Yeap, I agree with Migsel..and ask anyone who has tried to stay with mine, the siebenrock does make a big difference to an 80. All this frame and brakes not being able to handle it is tosh

MiGSel recently fitted the kit to his R80 g/s - bloddy thing goes like shit off a shovel now. He likes it ....a lot !!

 

[TERRY RYAN]

My ones matches all the above with a MATKAT
go faster Airhead sticker

 

[mikyh]

Mine also

Goes much better with the Siebenrock kit.

I have it for 4 years now. A lot more grunt down low, very good milage.
Recently i changed the rotting collector box with a Y piece. It started pinging like crazy on anything mor than 2/3 throttle. Uped the maint from 135 to 145 and all is well again.
The roar from full throttle exhaust became a music masterpiece.
Miky

 

[cookie]

Goes much better with the Siebenrock kit.

I have it for 4 years now. A lot more grunt down low, very good milage.
Recently i changed the rotting collector box with a Y piece. It started pinging like crazy on anything mor than 2/3 throttle. Uped the maint from 135 to 145 and all is well again.
The roar from full throttle exhaust became a music masterpiece.
Miky

is this on an R80 or R100?

 

[mikyh]

was 800

I think the standard Siebenrock kit works best on this conversion, using the smaller 800 valves and carbs to gain mixture speed and better combustion.

For the really ambitious, they have a full kit, complete with camshaft etc.
Look it up in their site.