Suzuki GR650 - back to work...

[Big R]

Re: Suzuki GR650- change is in the air.......

Remember Ben - it's practically the same bike. I looked at some "modern" Suzuki fairings and they just wouldn't look right on an older model IMO. Then I looked at some much older style fairings (Dunstall, Rickman, Vesco, etc) and I don't think they would be proper either.

The GS500 fairing seems to be a perfect compromise : round headlight, perfect width around the motor, really close height-wise, and it's fairly inexpensive if you order their package deal. I did a MSPaint version of the fairing on the GR.......let me see if I can find that.......

 

[ben2go]

Re: Suzuki GR650- change is in the air.......

Remember Ben - it's practically the same bike. I looked at some "modern" Suzuki fairings and they just wouldn't look right on an older model IMO. Then I looked at some much older style fairings (Dunstall, Rickman, Vesco, etc) and I don't think they would be proper either.

The GS500 fairing seems to be a perfect compromise : round headlight, perfect width around the motor, really close height-wise, and it's fairly inexpensive if you order their package deal. I did a MSPaint version of the fairing on the GR.......let me see if I can find that.......

You do make a good point there.

 

[gr650tempted]

Re: Suzuki GR650- change is in the air.......

what is you final jetting as far as carbs with the pods and exhaust? I have a tempter that i am converting into a cafe. Any info would be appreciated, Thanks

 

[Big R]

Re: Suzuki GR650- change is in the air.......

what is you final jetting as far as carbs with the pods and exhaust? I have a tempter that i am converting into a cafe. Any info would be appreciated, Thanks

Honestly? I can't remember the exact numbers. I bumped the pilots up one size, and one of the mixture screws (that are covered by that "cap") were stripped out. So no adjusting that one...... I used the stock needle which isn't actually adjustable. But it does have a plastic spacer on TOP of the clip on the needle - so I put that spacer below the clip. The mains were BIG.......somewhere around 165 ish?

I was experimenting with the mains as best as I could along with other stuff, and I just ran out of time. There is a guy on the GR forum (I think it was Spitse) that had pods and open pipes. He listed his jetting as well.

 

[Kanticoy]

Re: Suzuki GR650- change is in the air.......

Oh yeah, I think that will certainly be the tits.

 

[JustinLonghorn]

Re: Suzuki GR650- change is in the air.......

Looks good to me.

 

[peteGSX]

Re: Suzuki GR650- change is in the air.......

All good Rich, I must confess I haven't gone through the earlier bits of this thread in detail so may have missed you mentioning the GS500 fairing, but yeah it should work well

I've got no plans for any of my old 450's bits yet, so that fairing is just sitting as is the stock airbox and mudguards and things...

If you decide you want it let me know and I'll get a more accurate idea on shipping costs for ya

At one point I thought if I did the YB100 up as a bucket racer I might use the fairing on it, but that's now a pipe dream as my wrist won't cope with that low down action so it'll definitely be a spare item...

 

[Big R]

Re: Suzuki GR650- change is in the air.......

Finally dug up that pic. I made this on MSPaint and I'm not very good at it - so the scale is off along with the angle........but you guys should get the idea.

 

[gr650tempted]

Re: Suzuki GR650- change is in the air.......

Spitse only went to #140, you went a lot higher. I noticed though that he has the stock boots from the airbox...have you tried just the filters on the carb throats? If so how did it do?

 

[Big R]

Re: Suzuki GR650- change is in the air.......

I tried that as well, but only for a day. So there was no actual messing with jets.

The reason I went so far past 140 was I kept getting some high speed popping. But I think it was a reverberation from the muffler. The SuperTrapp I was using had the minimal amount of discs in it. After messing with the muffler and the jets, I was definitely rich at high rpm. But not enough to bog down or anything.

 

[Maritime]

Re: Suzuki GR650- change is in the air.......

a little rich s better than lean, worst case is you use a bit more fuel ... lean can mean a piston exits stage left. I like the look of the fairing. can't wait to see it in real life.

cheers

Maritime

 

[Big R]

Re: Suzuki GR650- change is in the airBOX.......

Ok, I've decided to follow the advice of EVERY cycle engineer and run an airbox. But as we all know, stock doesn't rock. I just want to point out - this is a PROTOTYPE. The carb ports and frame mount is from the original GR airbox, the air filter and surrounding plastic is from a modern GS500, and the rest is just pieces of plastic welded together with a 40 watt soldering iron. The entire thing will be prettied up before Spring. Right now it slides into the frame, bolts up, and does not interfere with the seat pan (actually clears with about 1.5").

The guts:

And the assembled product:

In the frame:

 

[peteGSX]

Re: Suzuki GR650- change is in the airBOX.......

Interesting direction Rich, a custom going *back* to an airbox? Who woulda thunk it?


You do know that us backyard mechanics know more than any engineer right? ???

 

[kwazykid]

Re: Suzuki GR650- change is in the airBOX.......

Hmm, I find this interesting. Are you doing this because you are having trouble getting the carbs tuned? I'm no carb expert so no judgment here. I do actually like how the shape looks...surprisingly since I didn't like the original at all. I see potential. Way to push the envelope.

 

[Maritime]

Re: Suzuki GR650- change is in the airBOX.......

Nice Rich, you can actually paint numbers or someting on it and it won't actually look like an airbox. Or install some number plates on it to completely hide it.

 

[Hoosier Daddy]

Re: Suzuki GR650- change is in the airBOX.......

Tweeking a factory airbox is something I like to do myself, I think it's a good idea. I've read that on some engines the airbox keeps resinance down on the carbs due to being mounted together on the intake end as opposed to being unsupported individually using pods.
No proof, just theory.

 

[Kanticoy]

Re: Suzuki GR650- change is in the airBOX.......

Rich may be the smartest one here considering he's bit building a wot race bike. I think air boxes are smart. I want to do the same for my 400. I think there is much power to be gained and a lot of equilibrium through the throttle position to be had with a well tuned box. I've considered molding a few from clear acrylic for that wide open look! Good job brother. Looking good.

 

[JustinLonghorn]

Re: Suzuki GR650- change is in the airBOX.......

As much as we like the custom wide open look, I suppose that there was a reason for the bikes to have them in stock trim.

I really dig it man. I think it will turn your scoot into quite the performer.

 

[t71ford]

Re: Suzuki GR650- change is in the airBOX.......


A bunch of "cafe racers" we are...first fairings, now airboxes. What's next, softail suspension and Tour Pak? ;D

Nice work man, I really like the idea. Do you have velocity stacks inside the box, at each throttle body? Most of the stock boxes I have seen are set up this way, and they are tuned as well. It doesn't look like you have them in your pictures, and it might be part of your R&D, but here is what I mean. The inside of the airbox on the VTR. My XS1100 was the same way.

Really nice work fitting it in under the seat, and plastic welding too. This kind of thing is what makes this place interesting! Can't wait for test results!

 

[t71ford]

Re: Suzuki GR650- change is in the airBOX.......

I've considered molding a few from clear acrylic for that wide open look!

Cool idea! The only thing to work out would be how to keep it clean if it's visible. Seems like there are brown stains at the bottom of every airbox I've ever opened...