Race Bike Build - Oct 12th/13th due date

Hey guys building out a race bike for the Lafayette Oct 12th and 13th races and am tracking the progress here.

Goals: Win non-variated and unlimited class (Doug and Mars I'm coming for you.)

Phase 1:

Specs:

1. Pipe: hack/welded side bleed Leo Vince (hit way too late for track use)

2. Carb: 19 PHBG, (96 main, 45 idle, 60 starter, correct atomizer and 2t bushing.)

3. Intake: Velocity Stack and 45 degree aluminum intake mated to stock Gila 4 petal, 23mm ID hose, which tore and ended the racing after 1st run).

4. Gila 74cc Cyl TYPE A

5. Treats CDI

6. Magnum Swingarm

7. Pinto Inverted EBR (no cross-brace, was not fun).

8. Rear coil springs

Phase 2:

Specs:

1. Pipe: Derbi Zen 75cc chamber

2. Carb: 19 PHBG, (jetting TBD)

3. Intake: MLM spigot intake, Doppler "tuneable" intake, mounting surface matched to VFORCE 8 petal.

4. Gila 74cc TYPE A -- MLM Water Cooled Head, Laser Machine radiator)

5. Treats CDI, more aggressive timing

6. Magnum Swingarm

7. Tomos Revival front end, Spoked wheel

8. Rear coil springs

Phase 3: Swap parts onto a Tomos Revival frame- changes below. This is a "best-case" and dependent on timeline.

Specs:

1. Modular chambers, using Derbi Zen slip-header for easy changes

2. Tomos Revival Frame - Cross brace with knee pads for lateral control

3. Convert to wishbone monoshock with adjustable rebound

4. Lexan body panels

5. Adjustable rear sets, seat height/angle, clips ons(edited)

Re: Race Bike Build - Oct 12th/13th due date

Phase 1. Gearing/jetting/pipe was wrong for the track.

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Re: Race Bike Build - Oct 12th/13th due date

Dirty30 Dillon /

Doug is good, Doug is great, Doug wins races because he never sleeps in late.

Re: Race Bike Build - Oct 12th/13th due date

why is there no "like" function in marmy yet

Re: Race Bike Build - Oct 12th/13th due date

Overpriced Parts /

Is there a carb restriction size? Cause man, a mikuni tm24 really wakes up a Gila with 8 petal, 24mm Compared to the 19 mm is like 2more hp!

Re: Race Bike Build - Oct 12th/13th due date

> Dickie Thompson Wrote:

> -------------------------------------------------------

> why is there no "like" function in marmy yet

Because this is a forum . Take a second and proclaim your feelings , instead of the arduous action of dropping a finger .

Re: Race Bike Build - Oct 12th/13th due date

No restriction on carb. I had a 19mm handy and wanted to learn about multi circuit carbs.

Good thoughts there..maybe a 24 is the way to go

Re: Race Bike Build - Oct 12th/13th due date

cannot stress enough that the number one fuck up moped people make when building race bikes is spending thousands on their engine and putting on some cheap ass moped tires and not dialing in their suspension- races are won by carrying corner speed. Do whatever will help you brake later and get on the throttle earlier.

so on that note some thoughts:

1. Both adjustable compression and rebound damping are important. Especially when you're building an entirely new suspension linkage. You'll want to be able to manually adjust as well as spring tension for your weight.

2. spend time playing fork spring springs and oils to tweak those characteristics in the front. Moped folks seem to set their forks up to be waaay stiffer than optimal because I think the perception is that's better.

3. Get the widest and softest tires that you can fit and run them with way less tire pressure than you would on the street. My crf100 minigp bike with bt45s I run 17psi in.

4. read up on cornering theory and race craft, Keith Code's "Twist of the Wrist" is a must-read, and get lots and lots of seat time.

Re: Race Bike Build - Oct 12th/13th due date

Suspension info is good. Any recommended rear monoshock with adjustable rebound/damper?

I'm grinding some of my cylinder fins and Derbi Zen slip header to fit. I think I will need a slim nut or allen nut to clear it.

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Re: Race Bike Build - Oct 12th/13th due date

Following

Re: Race Bike Build - Oct 12th/13th due date

Mlm intake for spigot 19mm. Stripped the powder and marked off the ID of Vforce for better flow.

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Re: Race Bike Build - Oct 12th/13th due date

Unlimited printing at work ty for the recommendation

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Re: Race Bike Build - Oct 12th/13th due date

Well the boys and girls over at Zen cranked their mig up without a proper jig and warped the shit out of the flange

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Re: Race Bike Build - Oct 12th/13th due date

This guy just needs to be smoothed out to match my vforce

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Re: Race Bike Build - Oct 12th/13th due date

Dirty30 Dillon /

The Zen flange was fine, you want bow in that direction so that when you torque it down it pulls the center, then the ears tight to the mating surface.

Re: Race Bike Build - Oct 12th/13th due date

Yea we were weighing that last night as a purposeful design. It looked warped since the bow was uneven by 1-2mm. I was also skeptical on the strength of the gila threads to pull such a thick flange flush. Judging from the uneven cut on on the slip header and OK welding i figured it was just too much heat.

Re: Race Bike Build - Oct 12th/13th due date

This happened too.

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Re: Race Bike Build - Oct 12th/13th due date

Ana L. of the Aurora Roras /

JB weld

Re: Race Bike Build - Oct 12th/13th due date

I prefer the not flexed design. looks funs.

on andy's point about suspension; brakes too!

"Do whatever will help you brake later and get on the throttle earlier."

like having better brakes than a tiny leleu drum!

Re: Race Bike Build - Oct 12th/13th due date

In regards to suspension, get rid of all brake dive. If the track is smooth, I like a rigid feel. Loose suspension just gives off a wobbly feel.

Brakes, sipe your shoes, sand them to remove glaze, and sand the inner drum surface. Not alot, just enough to scuff up the shiny surface. You can make your lelue drums work perfect, despite what other people may say. (Mine will lock up the rear and stoppie the front if I want them to.)

Get compressionless cables and levers with the right pull.

Also, remove the red plastic plug and drill some little vent holes in the brake plate for some airflow.

Set up your handlebars for comfortable steering, not just for a low tuck straight line position. You want to be relaxed and comfy, not fighting your bike thru corners, and it helps with the death grip pain and numbness.

Get your bike as light as possible. Alloy rims help. Mags weigh a ton. Remove everything you don't need.

Gear for the track, not the street. If it's a short, twisty track, gear low for cornering speed. If it's got long straights where faster bikes always catch up or pull away, gear it higher to stay up front.

Same goes with pipes. Tight tracks, get the pipe to hit early as possible to stay in the powerband.

Re: Race Bike Build - Oct 12th/13th due date

> baird co Wrote:

> -------------------------------------------------------

> Set up your handlebars for comfortable steering, not just for a low tuck

> straight line position. You want to be relaxed and comfy, not fighting

> your bike thru corners, and it helps with the death grip pain and

> numbness.

totally

also a v common race moped mistake. If your ergos make you put tons of weight on your wrists or "death grip" them that's an indicator your shit is funky. It should be as easy to pull both cheeks off the seat into the lean as possible. If it feels awkward at all to do that, the ergos are wrong. Some reading on body position will definitely help inform geometry decisions.

also this thread is dope, keep updating as you do stuff.

Re: Race Bike Build - Oct 12th/13th due date

Thanks guys, loving the support here.

Running a disc revival spoked front end. Looking at that hydraulic drum conversion I saw in a thread to prevent hand fatigue.

Shortish gearing for sure. My original setup barely touched the pipe on the end of the straight away.

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Re: Race Bike Build - Oct 12th/13th due date

I wouldn't spend the time or money worrying about the rear brake- you shouldn't be using your rear unless you're trying to emergency stop because someone crashed in front of you or something.

Re: Race Bike Build - Oct 12th/13th due date

Good point..with everything going on in this build i have a running list of priorities. Ill bump that one down..

Re: Race Bike Build - Oct 12th/13th due date

New longer studs installed, base gasket (soaked in 2t oil for about 30 mins) head gasket, finished installing slip header, found that my doppler intake is in the way of my feet, reeds dropped in, head put on..

Nothing is torqued down. Getting some stud spacers for the head. Mounting the radiator..

That little fuel line quick release has yet to be tested. Should make tuning the carb much easier. 5/16ths was all I could find for cheap, getting it on the 3/16tha tygon was ultra fun.(edited)

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Re: Race Bike Build - Oct 12th/13th due date

I really don’t think building a fast bike will make You win. Yea it’s nice to have a really fast bike but you don’t need it.

They all just follow behind to hope that they get a chance for an opening. Basically who’s ever in front they will try to follow, so just ride like a crazy man and do the complete opposite and go on the out side and just goos that bitch in.

Re: Race Bike Build - Oct 12th/13th due date

> Rocco Taco Wrote:

> -------------------------------------------------------

> They all just follow behind to hope that they get a chance for an

> opening. Basically who’s ever in front they will try to follow, so just

> ride like a crazy man and do the complete opposite and go on the out

> side and just goos that bitch in.

you fully don't understand what you're talking about

Re: Race Bike Build - Oct 12th/13th due date

> Dave & Bummerzz Wrote:

> -------------------------------------------------------

> > Rocco Taco Wrote:

>

> > -------------------------------------------------------

>

> > They all just follow behind to hope that they get a chance for an

>

> > opening. Basically who’s ever in front they will try to follow, so

> just

>

> > ride like a crazy man and do the complete opposite and go on the out

>

> > side and just goos that bitch in.

>

> you fully don't understand what you're talking about

Your absolute correct I don’t understand why you wouldn’t try to change stuff up a little bit! I get style plays a big role in winning but fuck it dude. Y’all reminded me of those bicycle going down the street in a perfect line.

Make your own path inside following the leader. Pretty much just mess up the normal exercise and that alone will confuse them and give you a winning spot.

I watched threekneedown and he was getting the idea. You gotta be fucking aggressive out there

Re: Race Bike Build - Oct 12th/13th due date

> Rocco Taco Wrote:

> -------------------------------------------------------

> Your absolute correct I don’t understand why you wouldn’t try to change

> stuff up a little bit! I get style plays a big role in winning but fuck

> it dude. Y’all reminded me of those bicycle going down the street in a

> perfect line.

>

> Make your own path inside following the leader. Pretty much just mess up

> the normal exercise and that alone will confuse them and give you a

> winning spot.

>

> I watched threekneedown and he was getting the idea. You gotta be

> fucking aggressive out there

I'm not really clear on what you're trying to say.

There's a lot to race craft and strategy and you don't appear to be familiar with it on a pretty fundamental level.

Re: Race Bike Build - Oct 12th/13th due date

> Dave & Bummerzz Wrote:

> -------------------------------------------------------

> > Rocco Taco Wrote:

>

> > -------------------------------------------------------

>

> > Your absolute correct I don’t understand why you wouldn’t try to

> change

>

> > stuff up a little bit! I get style plays a big role in winning but

> fuck

>

> > it dude. Y’all reminded me of those bicycle going down the street in a

>

> > perfect line.

>

> >

>

> > Make your own path inside following the leader. Pretty much just mess

> up

>

> > the normal exercise and that alone will confuse them and give you a

>

> > winning spot.

>

> >

>

> > I watched threekneedown and he was getting the idea. You gotta be

>

> > fucking aggressive out there

>

> I'm not really clear on what you're trying to say.

>

> There's a lot to race craft and strategy and you don't appear to be

> familiar with it on a pretty fundamental level.

How is it a strategy if the guy behind and in front of you is trying the same thing? Mix it up a lil, worse thing that could happen is u Lose.(edited)

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