GT750 Phat Trakka - new video revised exhaust
- Thread starter teazer
- Start date
Re: GT750 Phat Trakka - one small problem
Rev,
I keep looking at that idea. I did contemplate making a C/F front plate and adding enough color to match it to teh rest. The original "plan" had white "plates" at the rear, but that changed....
I weighed it this morning and must have screwed up, so I'll weigh it again when there's someone around to steady the bike. I don't think it was level because it rear 212 pounds on the front end and 168 at the rear. That's a total of only 381 versus a stock 536 with no gas which is a sort of average of test reports from back in the day.
There's no way it dropped 165 pounds. Front end dropped around 5-15 with lighter rim, disks, calipers and headlight and gauges. The motor probably dropped 10 lbs or so with lighter barrels and no starter or gears/clutch. Exhausts must weigh 30 pounds less, plus some of the rear end metal would add up to about 60 pounds I guess - not 160 so I need to weigh it again. I'm guessing I miss read the scales the first time. Which goes to prove the fact that you can't just grab one piece of information and treat it as an absolute truth.
Pete. Thanks
Rev,
I keep looking at that idea. I did contemplate making a C/F front plate and adding enough color to match it to teh rest. The original "plan" had white "plates" at the rear, but that changed....
I weighed it this morning and must have screwed up, so I'll weigh it again when there's someone around to steady the bike. I don't think it was level because it rear 212 pounds on the front end and 168 at the rear. That's a total of only 381 versus a stock 536 with no gas which is a sort of average of test reports from back in the day.
There's no way it dropped 165 pounds. Front end dropped around 5-15 with lighter rim, disks, calipers and headlight and gauges. The motor probably dropped 10 lbs or so with lighter barrels and no starter or gears/clutch. Exhausts must weigh 30 pounds less, plus some of the rear end metal would add up to about 60 pounds I guess - not 160 so I need to weigh it again. I'm guessing I miss read the scales the first time. Which goes to prove the fact that you can't just grab one piece of information and treat it as an absolute truth.
Pete. Thanks
Re: GT750 Phat Trakka - Almost ready to rock
Thanks, I can't get over how much taller the rear wheel looks. Both are 18" rims, but the comparison between a low profile front and taller rear is most marked.
That front was a flat, race plate that I bent to shape by heating along the bend line and bending it around a piece of 2 by 4, and then trimmed to a more modern/supermoto shape. The lights are a pair of fog lamps mounted one above the other on a custom bracket. Upper fork legs are pretty ugly on this model, so I modified the stock headlamp ears but doing a Van Gogh (cut off the ears) and welded on new brackets/spacer-mounts.
If your upper fork legs are clean and shiny, I'd use a GS/Bandit type mounts that fit between/inside the legs, so they are almost invisible.
This frame is not very svelte looking , so I elected to keep the side covers but moved them forward to fill the space where the air filter box used to be and made a pair of Carbon skins.
The idea was a totally streetable bike with the look of a Flat tracker but with all the "bits" necessary to make it a great road bike. BT45 tires, modern brakes wrapped around a more or less stock but lightened frame and fork combo. I can't use real flat track tires on the street and there's no way I'm trusting life and limb to any of the cheap fat tires. Frame and fork flex I can deal with but tires and brakes that don't work are not for me.
Thanks, I can't get over how much taller the rear wheel looks. Both are 18" rims, but the comparison between a low profile front and taller rear is most marked.
That front was a flat, race plate that I bent to shape by heating along the bend line and bending it around a piece of 2 by 4, and then trimmed to a more modern/supermoto shape. The lights are a pair of fog lamps mounted one above the other on a custom bracket. Upper fork legs are pretty ugly on this model, so I modified the stock headlamp ears but doing a Van Gogh (cut off the ears) and welded on new brackets/spacer-mounts.
If your upper fork legs are clean and shiny, I'd use a GS/Bandit type mounts that fit between/inside the legs, so they are almost invisible.
This frame is not very svelte looking , so I elected to keep the side covers but moved them forward to fill the space where the air filter box used to be and made a pair of Carbon skins.
The idea was a totally streetable bike with the look of a Flat tracker but with all the "bits" necessary to make it a great road bike. BT45 tires, modern brakes wrapped around a more or less stock but lightened frame and fork combo. I can't use real flat track tires on the street and there's no way I'm trusting life and limb to any of the cheap fat tires. Frame and fork flex I can deal with but tires and brakes that don't work are not for me.
Big R
Heaven is so far away.
Re: GT750 Phat Trakka - Almost ready to rock
Great stuff going on here Teazer! I see the fork brace, but are you opting for no front fender? I would want to keep all the road crud off that bike as much as possible (and protect that radiator).
This makes me want to put a little more effort into my own work.....
Great stuff going on here Teazer! I see the fork brace, but are you opting for no front fender? I would want to keep all the road crud off that bike as much as possible (and protect that radiator).
This makes me want to put a little more effort into my own work.....
Re: GT750 Phat Trakka - Almost ready to rock
Joey, Thanks mate.
Rich, I wanted to slip a cut down stock fender in there, but the front wheel is 18" and the old one was 19" and the radius is all wrong. Somewhere there's a suitable fender waiting for the opportunity to slip between those fork legs, but it has to be the right one.
I also tried a high mount and that just looked all wrong too. I'll keep looking for something suitable.
Joey, Thanks mate.
Rich, I wanted to slip a cut down stock fender in there, but the front wheel is 18" and the old one was 19" and the radius is all wrong. Somewhere there's a suitable fender waiting for the opportunity to slip between those fork legs, but it has to be the right one.
I also tried a high mount and that just looked all wrong too. I'll keep looking for something suitable.
Re: GT750 Phat Trakka - Almost ready to rock
Ah ha. Healthy skepticism wins again. measure the weight again with my trusty helper and the real number is..................................
441 pounds. That's a drop of almost 90 pounds from stock, so not too bad.
Differences include:
Alloy rims
Light disks
Lighter calipers
Tiny gauges and headlamp
Small battery
Alloy bars
C/F side covers
Lightened footpegs
Drilled footpeg bolts
Drilled rear axle
35 pound lighter exhaust
No electric starter, solenoid or wiring.
Lightened barrels and head
Lighter air filters.
Frame lugs lightened
There's a few pounds still to go in there 0- maybe it's time for some titanium...
These bikes sure are heavy
Ah ha. Healthy skepticism wins again. measure the weight again with my trusty helper and the real number is..................................
441 pounds. That's a drop of almost 90 pounds from stock, so not too bad.
Differences include:
Alloy rims
Light disks
Lighter calipers
Tiny gauges and headlamp
Small battery
Alloy bars
C/F side covers
Lightened footpegs
Drilled footpeg bolts
Drilled rear axle
35 pound lighter exhaust
No electric starter, solenoid or wiring.
Lightened barrels and head
Lighter air filters.
Frame lugs lightened
There's a few pounds still to go in there 0- maybe it's time for some titanium...
These bikes sure are heavy
Re: GT750 Phat Trakka - Almost ready to rock
Like this you mean?
Smoke Signals - GT750 Phat Trakka
The smoke is now cured, so next step is to dial in timing and drop a main jet size before I do some runs to break it in.
Like this you mean?
Smoke Signals - GT750 Phat Trakka
The smoke is now cured, so next step is to dial in timing and drop a main jet size before I do some runs to break it in.
Re: GT750 Phat Trakka - Almost ready to rock
Now I'm really pissed off. The tank has a tiny pin hole somewhere close to the new filler cap and the paint has gone soft and blistered slightly. The tank has been drained and put out in the sun for the last couple of days to bake any fuel fumes out of it and the paint has hardened up.
Now I need to scour the inner surface and do the Caswell liner again. I must have missed a tiny blow hole somewhere. Ah well, it gave me a chance to make a few other adjustments and get it ready for the dyno..
Now I'm really pissed off. The tank has a tiny pin hole somewhere close to the new filler cap and the paint has gone soft and blistered slightly. The tank has been drained and put out in the sun for the last couple of days to bake any fuel fumes out of it and the paint has hardened up.
Now I need to scour the inner surface and do the Caswell liner again. I must have missed a tiny blow hole somewhere. Ah well, it gave me a chance to make a few other adjustments and get it ready for the dyno..
Re: GT750 Phat Trakka - Almost ready to rock
that phat bitch is sexy! kinda jealous right now...not gonna lie. Well done!
that phat bitch is sexy! kinda jealous right now...not gonna lie. Well done!
Re: GT750 Phat Trakka - Almost ready to rock
Today I wanted to get an idea of how accurate or inaccurate the Trail Tech Vapor bar graph tacho is. I don't have a super accurate, calibration grade tacho, so I did the next best thing and hooked up a couple of other tachometers to use as a cross reference.
One was a simple TZR250 tacho with three leads and it turns out to be DOA. I should have tested it when it arrived. Ah well. That's ebay for you.
The next one I hooked up was a huge Polaris snowmobile 6 pulse tachometer. I like the in your face look of that tacho and it reminds me of a Vincent 5 inch speedometer (from a distance). It has two wires, one is to ground and the other is to the alternator, so I hooked that up to one of the three yellow leads from the GT alternator to the rectifier.
I fired the bike up and at a steady, 2000, 3000, 4000 revs both tachometers read the same. The Polaris XCR800 triple tacho appears to be a little over damped and rises rather slowly so it's probably not a great idea for a fast revving race bike, but for the street it would look great on a street tracker for example.
If you like the look of a large tacho dominating the bars, it's killer. If you want subtle and hidden it's not for you.
Today I wanted to get an idea of how accurate or inaccurate the Trail Tech Vapor bar graph tacho is. I don't have a super accurate, calibration grade tacho, so I did the next best thing and hooked up a couple of other tachometers to use as a cross reference.
One was a simple TZR250 tacho with three leads and it turns out to be DOA. I should have tested it when it arrived. Ah well. That's ebay for you.
The next one I hooked up was a huge Polaris snowmobile 6 pulse tachometer. I like the in your face look of that tacho and it reminds me of a Vincent 5 inch speedometer (from a distance). It has two wires, one is to ground and the other is to the alternator, so I hooked that up to one of the three yellow leads from the GT alternator to the rectifier.
I fired the bike up and at a steady, 2000, 3000, 4000 revs both tachometers read the same. The Polaris XCR800 triple tacho appears to be a little over damped and rises rather slowly so it's probably not a great idea for a fast revving race bike, but for the street it would look great on a street tracker for example.
If you like the look of a large tacho dominating the bars, it's killer. If you want subtle and hidden it's not for you.
Re: GT750 Phat Trakka - Almost ready to rock
Tank has been drained and blown through. Then I sat it outside in the "solar oven" to bake those fumes out in the summer sun for a few weeks. Then I mixed up another half can of CAswell expoxy tank sealer and added that and left the tank upside down after it had been slowly turned a few times.
I had to be careful not to get too much sealer in one spot because it gets really hot if there's too much, so I monitored the temperature as it started to set. Then it was left for a few more sessions in the solar oven to bake off any epoxy fumes and to fully cure the sealer.
The petcock was replaced with a new GSX tap an that fixed that leak.
Next issue is the clutch release which still isn't as smooth as I'd like, so I'll drain the trans oil and strip out the lifter mechanism and I'll replace the two seals in there just in case they were damaged on assembly. Need to order them ASAP.
I'm still not happy with the water pump so I' may swap that one out before we head to the Dyno for a workup.
Tank has been drained and blown through. Then I sat it outside in the "solar oven" to bake those fumes out in the summer sun for a few weeks. Then I mixed up another half can of CAswell expoxy tank sealer and added that and left the tank upside down after it had been slowly turned a few times.
I had to be careful not to get too much sealer in one spot because it gets really hot if there's too much, so I monitored the temperature as it started to set. Then it was left for a few more sessions in the solar oven to bake off any epoxy fumes and to fully cure the sealer.
The petcock was replaced with a new GSX tap an that fixed that leak.
Next issue is the clutch release which still isn't as smooth as I'd like, so I'll drain the trans oil and strip out the lifter mechanism and I'll replace the two seals in there just in case they were damaged on assembly. Need to order them ASAP.
I'm still not happy with the water pump so I' may swap that one out before we head to the Dyno for a workup.
