Cams anyone runnin GSXR 750 cams ?

[RacingJake]

I was going to try the same thing with just the rear tail light assy. Look like it would work with some tabs welded on the frame. But I never got around to it and just chuck it. Plus I already cut most of the frame off past the shock mounts. But it should be do-able.

[U.P.dragracer]

Back to the cam story , after instaling the exhaust cams the engine sounded real tuff and ran nice but it lost some top end power . it did help with my 1/8th nile and 60 ft times but lost some top end charge it had with the intake cam only configuration . the bike ran 10.30's last weekend and could only muster a 10.52 this weekend . the weather conditions were almost identical again . 1/8th mile mph was on par but 1/4 mile speed was down 2 to 3 mph . :shock:

I'm going to yank out the exhaust cam and run the stock exhaust cam . I'm thinking the stock compression and cylinder head porting is not up to par to take advantage of more lift and duration on the exhaust side .
I think if I was to play with the lobe centers I might be able to make the exhaust cam work better but not worth the effort , when simply putting the stock exhaust cam in will net me some decent results .\\/

[RacingJake]

That's interesting on the exhaust cam swap?? I'm using a 280 lift exhaust cam and the bike runs great with this small cam. Maybe the 25mm exhaust valve's in the 750 head makes up for the small cam?? or maybe it's the compression??

I want to make a few run with the bars on (when it quits raining) with these cams, then swap over to the 340/320 one's and compare them.

[RacingJake]

I don't know the rocker ratio on this Katana head but I measured the 340/320 cams base circle then the lobe height and with the lift I times it by 1.5 and I was getting 350 on the intake and 330 on the exhaust ????

[rapidray]

That is correct Jake. Ray.

[RacingJake]

Thanks Ray, that's what I was thinking too.

It sure would be nice if Suzuki would stamp some number other than 27 on all these cams to tell what size they are........ but who I'm I to say

At least cam motion has the right idea

[QuaiChangKane]

Anyone know if specific GSX-R cams are drop-ins for a 750 motor?




And great returns on minimal investment, U.P.!!




-Q!

[Billy Ricks]

Anyone know if specific GSX-R cams are drop-ins for a 750 motor?




And great returns on minimal investment, U.P.!!




-Q!

If they will fit the big bore GS engines they will fit the 700/750 models as well. You can't run the really high lift cams for the big bore engines but stock, air-cooled GSX-R stuff should be okay.

[RacingJake]

Well from what I know and that's not alot is you can findgsxr/katana cams that are 350/330, 340/320 and 330/280 ..... may be more too.

I hear that GSXR cams will work in GS 4 valve head motor's. I've haven't try that yet but I think there are a few things you got to do to make it work.

I got a GS head on the bench..... give me a minute and I'll check it out.

[RacingJake]

The gsxr/katana cams are about 1/4 shorter on each end and the oil hole on the end caps are exposed, also the gsxr cams might need alittle work to due the the four inside cam caps are bigger than the gsxr one thus the cam may hit or rub the cam cap area too. Remove any high spots on the cam and four plugs at the end of the cams to keep the oil in there and should be doable???

[RacingJake]

Here a pic of gsxr cams in a 82 gs1100 head, interesting.

You can see the oil passage in the end journals may be a problem (rubber end plug ??) causing low oil pressure. Since the cams are not machine that far over in the middle journal a high casting mark may hit/rub that journal area?? Oil will bleed out of that journal too since the cams will not seat up agaisnt it and may cause low oil pressure??? The end caps may wear alittle faster due to less support of the cam.

Also the cam had .009 side play when the cam caps were bolted down. The g4 cam for a GS had .010