Options for a New 90 Mod Build

[bigdaddy77]

Im going to have to build a new 90 mod for tt and flat track racing. Doesn't need to be done this year but I'm wanting to gather some in put. Also I'm probably going to build another one for MX in a couple years. The problem is Adam is 9 and in the 3rd grade and is already 5 foot tall and 100 pounds. So the normal jb, Fischer, apex,etc. Builds are out.
Some of my ideas 400ex,250r, 450r and possible the 250 Raptor for flat track only. Don't think the Raptor frame would hold up as he grows and it's already about the same size as our pitsters.
Thanks and hope to get some good input.

[LT80]

Maybe JB's new 250 frame w/90 in it.

[bigdaddy77]

That is a option for our future MX quad. I also contacted Six5Design. To see what they had in the works. Thought I could get a frame and start buying the a arms and swinger, snicks,etc as money allowed.
But as far as a TT quad I was hoping to get some input about taking a production style quad and putting a 90cc motor to it. I know Roberts did some 400ex mods. Just trying to get some ideas and pros and cons. Thanks for the reply

[LT80]

I've seen a few 250'r and 400's (mods) on a TT track.
Usually way too heavy was the common result. :(
Blasters made into mods were a lil better.

Ask Rocky about his Can-Am modified that he built and the weight.

Best wishes on your build. :)

[hanker]

Most of the production type 90 mods are blasters from what I've seen at the EDT nationals. But there are some Fischers and JB's. Most of the ones that run that class are CVT's. There are a couple of Cobra's to.

[fish-d-fish]

If budget is not a problem try a walsh or leager trx 450r frame for TT with the 90 in it, make brackets for the motor using stock mounts, drop a 4 stroke 250 in it in 2-3 years and then the 450

[Logan #34's Dad]

The CanAm DS450 is by far the lightest full size chassis out there. And they are easy to convert to a mod(now that I've done a couple). My Mod weighs less that a JB and others. If your rider is big or gonna be big...I recommend the DS450 chassis.
The KTM chassis is also light...It's made from chromoly...since it's a mod you can weld tabs on the frame to accept any plastics. Cause KTM is UGLY! :blah:

[bigdaddy77]

Thanks for the info guys. For the TT Mod I think I'm going to go ( I hate to say it) but the blaster route. Maybe a 250 Raptor if I can find a chassis cheap.if any one has any info on the blasters as far as what a arms and especially the swing arm. Like stock length swinger or -2 or what for TT I'm all ears. I would like to upgrade the rear brakes to disc and possible the spindles hubs and front brakes.
Rocky as far as a future MX Mod what is the Can Am frame made of? What are you doing as far as suspension? I know Six5Design has come out with a arms and swingarm. Ronnie Higgerson is running it in the pro class. Any info would be great. We are hopeful going to run Balance at the end of April so I would like to get a good look at yours Rocky. Thanks again for the input.

[LT80]

The can-ams I know of have all suzuki front end stuff (spindles/rotors/brakes/etc) with JB arms.

[Logan #34's Dad]

The CanAm is basically square tubes of aluminum bolted to the side hips and bottom tray.
I use the stock A-arm and swingarm. Don't waist your money on the aftermarket a-arm or swing arms.... a factory CanAm mechanic from last year told me that they'd rather run the stock XMX a-arm over any aftermarket ones but are obligated to sponsors. We choose to run Fox shox. Again, fronts are very light and don't have the be resprung as he grows just the air needs adjusted. Rear Podium shock was revalved and resprung be Fox in Mn. They ran the stock swingarm and XMX axel.So, you can buy a XMX chassis or complete quad and go race.

[doonanracing]

For TT. 2 National Past Champions used a Blaster Chassis with a 90 motor in 2010 and 2011. One used a Yamaha the other a Suzuki as far as motor goes using a 90cc dirt bike motor. The supermini Champion from 2012 was in a Blaster chassis. The Blaster has been proven to work in TT Racing. For MX I might suggest a different route but for weight which is important in TT it can work. There is another National 2012 champion who's family is buiding using a Blaster Chassis now. As far as size of a child one boy was almost 6 feet tall whom rode a Blaster mod last season. The issue is weight. From a 400ex to a 250r or 450r you are dealing with weight issue with a 25HP 90 motor trying to pull it around the track at top speeds and a blaster is the lightest option right now versus a JB type mod which is always the best option. Parts also are cheap and costs effective for suspension etc. You will also need to be able to fabricate some parts to mount a radiator and engine mounts in whatever decision you make other than the JB mod which is normally built to your specs.
For set up you want the axle to sit directly underneath where the rider sits so you might need to get a shortened swingarm if you decide on the Blaster. For rear end set up a cheaper alternative also is using Banshee rear end parts which can fit in a Blaster which also changes the wheel bolt pattern for the Blaster which is uncommon if you go that route.
AS an FYI we had a 400ex mod build by Fisher which was an incredible build but son was no where as fast on it as in the JB mod we had as it was easier to ride and th 90 motor never seemed strong enough to pull the weight of the 400ex chassis around

[bigdaddy77]

Thanks for all the info guys. I Just got done building the Pitster 90 Mod and I guess I'm itching to start another build. The reason we went the Pitster route was because we have Christian Horne's original 4 stroke to run 90 production locally and the 125jr at a handful of Nationals. So we Gary offered me the 90 mod that I helped mock up at a reasonable price we went with it. My thought was it would make good sense to have identical chassis with different powerplants.
When we got the mod everything was bolt on because Gary was hoping to swap motors back in forth to run production and mod. I tore the whole quad down this winter and fabricated all chromoly.motor mounts along with all the other brackets and removing the unnecessary brackets. I need to figure out how to resize the pictures it turned out sweet. The AtvFourPlay suspension is awesome. The only knock on it is the turning radius and we are working on improving it and we slowly have been eliminating the Chinese brake components and.going with Honda parts. So any how we are set for a few years but I am always planning didn't the future. Might go a Roberts racing mod route in a few years.
Now on the flat track side we are going to have to address that in the near future. The Xtreme with the 4 cart tires and all the custom machine work is Just awesome. But it is quickly becoming to small.and we are at the limit for hp out of the little fourstroke.
So a Blaster TT mod here we come. I'm not going to break the bank but I am going to do it right. I'm thinking chromoly a arms and swing arm. Up graded front and rear brakes and not sure on the dirt bike powerplant.if any one has some info on the best setup I would love to here some suggestions. Also on lowering the ride height wheel and tire sizes etc. Again this is a TT build. We love to MX but Adam also enjoys the flat track racing and is actually a lot faster at it. 3 local tracks running it all summer + the Indoor Winter Nationals a hour and a half away. You do the math.lol Thanks guys

[Logan #34's Dad]

Does he fit the Pitster well? Reason I ask is becausethat chassis is much lighter than a blaster. Pitster is all chromoly and very strong from the factory.

[bigdaddy77]

He fits the Pitster about perfect. Still can't manhandle it like he can the Xtreme but getting better. I have a stock Pitster we trail ride. I don't really want to give it up to the TT build.or I should say Adam doesn't. Also the down falls are the turning radius, ride height, I could sub frame it to lower seat height.and the only a arms available are the AtvFourPlay..I found a bunch of frames locally for the Blaster dirt cheap.might pick one up and see Just how heavy they are. Deister and a few others have proven you can win on them. And the amount of parts available is incredible.