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camshaft upgrade


berty

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time for some new camshafts into the 1170ET.

Plenty to choose from - so some advice required please.

am running rs mik 36's , standard newish valves, good condition rockers, foam filters, mid range stacks.

Any experience advice out here please.

Am not looking to make it go bang .

 

 

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The gsxr cams are shorter than the gsx...they do however drop into the gsx head ..... the inner 4 cam caps are doubled up on the gsx which will not work with the gsxr cams.... but..... The single cam caps on the gsxr will work . The cams being shorter will sit about 70 percent of the outer bearing surface on both sides .

IMG_1521.JPG

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I don't know about the CR of your bike, but engines with a low CR cams with a lot of timing won't work.

For example, a GS1000 with stock pistons and a 184 degree cam will not work, it makes the bike slower instead of faster, put high CR pistons in it, and goes like lightning.

Do your home work before ordering

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14 hours ago, no class said:

The gsxr cams are shorter than the gsx...they do however drop into the gsx head ..... the inner 4 cam caps are doubled up on the gsx which will not work with the gsxr cams.... but..... The single cam caps on the gsxr will work . The cams being shorter will sit about 70 percent of the outer bearing surface on both sides .

Hmmm - subject to the lift available compared between the two, i'd almost be tempted to try them. The GSXR cam caps show that the GSX width ones were 'over engineered' so as long as the cams enclosed the oil ways they should work.

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but remember that the over engineered gsx cams werebuilt for an engine running considerably lower oil pressure than the gsxr engine delivers, perhaps the wider cam caps were designed with lubrication in mind rather than strength to hold the cams down. gsxr pumps deliver vast quantities of oil at high pressure, the gsx pump delivers low volume and low pressure, due to the roller crank. reducing the bearing surface area in the head might be a problem in use.  it may all be ok, but im just pointing out that the wider bearing areas on the aircooled motors may be to provide adequate lubrication.

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22 hours ago, berty said:

anyone had experience with the two types available from kent cams - street type and race type.

 

I have SPS JR3 cams in my 1360cc EFE. SPS cams are grinded by Kent Cams, I think the JR3 cams are close to the Kent Cams street grind.

Dyno results with stock cams (thin lines) and JR3 cams (thick lines).

pasi%20vapari%20verrokit_zpscpip7sgc.png

Edited by Blower1
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18 hours ago, johnr said:

but remember that the over engineered gsx cams werebuilt for an engine running considerably lower oil pressure than the gsxr engine delivers, perhaps the wider cam caps were designed with lubrication in mind rather than strength to hold the cams down. gsxr pumps deliver vast quantities of oil at high pressure, the gsx pump delivers low volume and low pressure, due to the roller crank. reducing the bearing surface area in the head might be a problem in use.  it may all be ok, but im just pointing out that the wider bearing areas on the aircooled motors may be to provide adequate lubrication.

In both motor designs the oil flow to the heads is restricted with brass drilled plugs the cases - identical flow due to cam bearing tolerances / design being identical. Lower pressure pump only used due to splash fed roller bearings, shell bearings need higher hence difference.

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19 hours ago, Gammaboy said:

Even better than EFE cams are Popup Kat cams from the non-restricted market bikes.

So does this mean 750 esd cams fit old gsx motors and work better  than efe ones ? Thought the esd motor was nearer to the gsxr than gsx and similar issues as stated above trying to use gsxr cams ?

 

 

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Couple of bits that I seem to remember about the Phase One bikes are that you need to be careful with the lift.

I seem to remember that EFE exhaust was as far a you could push if you wanted the stem seals to remain intact, but you could go a bit further on an inlet and get something from Piper etc.

Full stage 2/3 needs new, shorter valve guides.

Russell B has a loathing of moving guides in an Endurance engine, sustained high speed running has a habit of making the things drop out, which is slightly detrimental to reliability. Getting the tolerances right after pushing a factor fit one out of the head could be a little hit and miss.

But, his experience, has him thinking about running an engine at full, fuck you, mode for 24 Hrs, which is hardly likely for most people in the real world.

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  • 4 weeks later...
  • 5 years later...

Old post I know.

Above mentions 750 ESD cams cross over to the 1100.

But the 750 has 34.910mm inlet and 36.060mm exhaust lift.

1150 has 34.95mm inlet and 34.640mm exhaust

750 Inlet has similar lift to the 1150cams, but exhaust has less.

My question is, how would running the 750 cams in a 1150 motor change the power?

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