wanted: jemco pipes for gt 750.

[aslsmm]

hello. just looking to see if anyone is selling or parting out or has an extra set that they would want to sell. 625 is what they are going for new on jemco webpage. thanks.

[tz375]

Only looking for JEMCo pipes or looking at other makes of expansion chambers? There are other pipes out there, but admittedly they will be older but probably cheaper than JEMCos.

[aslsmm]

the jemcos come the highest reccamended by the guys that i have been talking to in regaurds to the build. i have some old factory pipe expansion pipes that i am going to sell. i am in this too much money now to cut any corners. i just scored a tr750 front fairing off of CL for 200 with a windshield. its a raged edge racing brand one. they don;t make it any more since their shop burnt down.

[tz375]

They are not bad pipes, but not the only choice.

Just out of idle curiosity, have any of the guys you spoke to dyno tested any of pipes? The reason I ask is that there is a lot of hearsay and not a lot of facts out there. I had one bike that came with two sets of pipes. The owner told me that there was basically no difference on the street as far as he could tell and yet on the dyno, the difference was huge from 4500 up. His butt was calibrated like most of ours - not well.

We rarely ride at WOT and even less often at peak RPM so most of us are not riding hard enough to tell much of a difference. What that guy was picking up on was the reduced weight and that made the bike feel much more perky.

If you have FPP chambers, they used to have a great reputation and tested well on other bikes.

[aslsmm]

ya know i am not against a good ol fashion phone call. i don't want to bug you but i would rather spend less if i can. now my pipes are beat up rather badly but if i can fix them cheaper than buying new ones im fine with that. the pipes will mostly be hidden by the fairing anyway.

like you said there is soooo much hear say.

if my FPP pipe will suite just as well then i will remove the dents and fix them. thanks for your input.

[oldjapanesebikes]

If you have FPP chambers, they used to have a great reputation and tested well on other bikes.

FPP ?

Never mind - did some digging and found the old thread.

[tz375]

FPP Factory Pipe Products. Their mufflers clamp on and look less sophisticated but I believe that the Yamaha twin pipes were Toomey designs and the 750 pipes may have been as well. On the RZ they made more power than any other pipes at that time.

There's no guarantee that the GT750 pipes were as good, but what you have is usually cheaper than buying replacements.

I don't know if they will be compatible with Eric's porting, but probably a cost effective place to start.

[aslsmm]

you know i believe that eric said his porting would work with other pipes, he just ports to jemco spec cause thats his preference. if the measurments of the FPP's and jemcos are the same then it stands to reason that they porting would work with both right?

[tz375]

Different pipes will work but they work differently. For example on the TZ, FPP used to make more top end and lost some at teh bottom compared to other pipes. J&R typically make more peak HP than others but at lower revs and are very peaky so they sign off fast.

Bassani are similar to JEMCo. And different porting works differently with different pipes and not always the way that you might expect.

I'll get back to you on those FPPs

[aslsmm]

i really appreciate all your help. this bike is going to come out amazing. thanx to all you guys and your help.

[aslsmm]

this is from tz 375. he did me a huge favor and here is what we found.

So I ran the numbers as best I could ascertain from your PM and adjusted for ID rather than OD, so there's some assumptions here.

The data on a ported motor worked out to more or less the same as Bassani and modified J&R and slightly more power than JEMCo but peak at around 6,000 and all done by 7,000. JEMCO would make less power but keeps revving a bit longer according to the numbers.

That was all on the same ported motor with different pipes but those ports will be different to yours, but the comparison won't change by much.

When the barrels come back from Eric and you get it built, then I'd like to hear how those FPP pipes work for you in the real world.

Richard


close thread.

[cwiseman]

I have a set of nos FPP'S but missing one silencer! If anybody comes up with one please PM me
Thanks so much