YZF750/1000R - The Fly 5

irk miller said:
I've repaired a bunch of plastics with G/Flex. You can use pigments to color match. In fact, most 2 part epoxy and plastic can be pigmented.

I ordered some, just the small bottles.
 
Another upgrade I'm doing is swapping out the intake runners for a set from a later model. The 94-95's didn't have air tubes on each intake, making carb syncing much more tedious and iffy. 96-98's had the air tubes on all the intakes so I got a used set from the net. They are grubby but in nice shape. This way, you can run a hose from each one , into the engine bay away from the carbs and boom I'll have individual sync hoses.
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I think on most carb syncs the nozzle(?) that goes in the end of the tubes needs to be within a certain proximity to the vaccum source to work properly, might want to check on that for your tube length.
 
https://www.cbperformance.com/product-p/6537.htm

Length of hose won't make a difference, as the vacuum will read the same. IMO, an SK flowmeter is the best option for syncing carbs. It's testing for airflow and has greater accuracy.
 
Irk, that tool you posted is pretty sweet. Mine is a Motion Pro though but it does let me sync with the airbox on. Doc, it actually comes with fairly long hoses. The pic i posted of the hoses is from my 97' stock yzf parts bike so those are stock length. Seeing the newer setup on the 97 is what made me decide to buy the newer intakes for the 94'
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In the instructions on the motion pro and on the Morgan carb tune, iirc both state the little nozzle you poke in the end of tube needs to be within a certain distance to the vacuum source to function correctly. I dont know how important this is but both carb syncs I have owned stated this.
 
I'll check on the total hose length when I go to setup the sync.

Until then I've decided that G/flex and fiberglass cloth was the way to go for this repair.
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Impromptu bike stands. The two engine/frame mounts used for the frame sliders are perfectly symmetrical and hold it just the right height.
Front wheel is off for the new Dunlop swap asap.
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What ever works man. I have hung bikes off the rafters with ratchet straps before.
 
Nice. G/flex is awesome. They recommend sanding plastics with 80 grit then a light flame polish with propane for the best adhesion.


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I have used jack stands, hung em from the rafters like Doc said. Whatever works man. I have a pit bull front stand now and man it is nice. I think I am going to get the Q3+ Dunlops.
 
I have a front and rear set of Pitbull stands. The rear of the bike is up on one. The front stand that has a pin and goes into the bottom of the neck doesn't fit this bike because the front fairing is too low. I have another front stand that uses the lower fork stanchions but you cant get the axle out with that stand in the way.

Man, I've wanted to do an overhead lift in here so I could hang stuff and pull motors right over my bench. Someday.
 
The front wheel on this bike already had a pretty decent shape Shinko Raven on it but I wanted the front to match the rear. I haven't tried the Q3's. These are Dunlop GPR300's. They were on sale at Revzilla when I got them. I think I paid about 220$ shipped for the pair. I take the wheels and tires for mounting to the oldest Yamaha dealer in the USA. Bobby J's Yamaha, here in Albuquerque.
 
I lurk Craigslist a lot. Another running parts bike showed up so today I pounced on it. It was 70 degrees in town this week but this bike was located three hours west of me and off the main road. It made me work for it. Not long out of town the weather turned and as I got closer to the rendezvous point , the snow was coming down and I found my self driving in a few inches of slush and powder on a two lane road. My van is only a half-ton and totally empty inside. Traction is precious thing, but about what I expected in those conditions. I did not get stuck and I brought home YZF750R #4. It should run after I unfrack a few things the PO did.
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doc_rot said:
In the instructions on the motion pro and on the Morgan carb tune, iirc both state the little nozzle you poke in the end of tube needs to be within a certain distance to the vacuum source to function correctly. I dont know how important this is but both carb syncs I have owned stated this.

It’s less about the distance and more about the volume of the hose.
If the volume is to large, the vacuum signal gets lost, it’s harder to sync.

It’s not a constant vacuum, it’s vacuum and pressure pulses. So if the volume/length in the hose is too large compared to the intake volume then you don’t have the same pressure drop you would with a smaller hose. The signal is harder to read.

Tl;dr the hose length is a valid point to consider, all lengths need to be somewhat similar.
 
Nice score on #4 ! You make me wonder if I have had the Gsxr on that pit bull with the fairings on.. ???
 
farmer92 said:
It’s less about the distance and more about the volume of the hose.
If the volume is to large, the vacuum signal gets lost, it’s harder to sync.

It’s not a constant vacuum, it’s vacuum and pressure pulses. So if the volume/length in the hose is too large compared to the intake volume then you don’t have the same pressure drop you would with a smaller hose. The signal is harder to read.

Tl;dr the hose length is a valid point to consider, all lengths need to be somewhat similar.

This made a lot of sense to me. Thanks Farmer.
 
1fasgsxr said:
Nice score on #4 ! You make me wonder if I have had the Gsxr on that pit bull with the fairings on.. ???

Thanks!. Check the fit. I would have seriously damaged the front fairing if didn't look carefully first.
 
i went and looked at the instructions for the carb sync and the nozzles in the ends are dampers, they need to be the correct distance from the carb sync to smooth the vacuum pulses out, on mine its 90cm away from the tool. the motion pro may be different. It sounds like you can add some tube in front of that and be fine.
btw that van is awesome.
 
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