What frame to use?

[DGardner]

I'm thinking about building a bike to use for the Bad Rock ride next year. The question I have is if you could start with a 03 frame or a 74 super combat, what would be the best one to use? Also what bottom end is the best to start with a 94 or the 03?

[Bullfrog]

Oooooooo, Doug - those are interesting questions. The answers, of course, all start with, "Well, it all depends on your personal preferences and what you like - but . . ."

But what the heck - I'll jump in and offer up some thoughts.

Frame for a Bad Rock Trail Ride bike? 03 or model 97? Um, neither. Model 94 or 95 (Wombat or Combat Wombat) is what I'd start with. Those two frames are exactly the same except the 94 has more brackets for street stuff. Why would I pick that frame? Lighter and lower seat height than the 03, but with new steering stops and longer shocks will work well with the 03 forks and triple clamps. If had to choose ONLY between the 03 and model 97 frame - I think I'd go with the 03 cuz it is ready to go with the 34mm forks. The 97 frame gets a downgrade from me for trail use because the engine is mounted fairly high in the frame to provide room for the original low pipe. There are a host of other factors which may be more important to you - things like rubber swing arm bushings on the frames I like or metal swing arm bushings on the two frames you asked about.

Which bottom end? Again, it all depends . . . The primary kick feature of the 03 is very, very nice to have, but most folks end up building a custom crank shaft using the Road Toad crank halves with a 94 con rod to allow the use of "normal" Hodie 125 pistons. The 94 bottom end allows for a wider selection of primary gear ratios and larger pool of used(and new) parts.

Have fun with the new project!
Ed

[DGardner]

I really like how Bob Canfield had his bike set up....was it a 03 frame with a 250 swingarm?

[Bullfrog]

Sorry, I don't have the details on that scooter. Though I wonder whether or not it might be easier to modify the 03 swing arm to the spec you want than it is to modify the 250 swing arm to fit the 03 frame.
Ed

[Jack Elliott]

Just one more question re frames
Is the Dirt Squirt frame the same as Combat Wombat?

[Bullfrog]

Yes, but with a shorter swing arm.
Ed
PS: Speaking of the toaster tank squirt that is.

[Jack Elliott]

Thanks Ed
I am occasionally daydreaming (and collecting parts) for an "improved" 125 enduro with the chrome tank squirt frame with 18/21inch wheels 34mm forks and extended swing arm - (The standard wombat swing arm makes for fun riding but its twitchy) reeded CW top end, wombat bottom end I am also planning on using a modified wombat air cleaner with a differnt element that will allow me to drill more breathing holes in the inside cover plate. I have heard that there is a custom element available from SH for this? Would like to test it out on my reeded wombat with 24mm carb also.
All this has to wait till the Super combat project is completed.
So much to do.
I am going out to the shed.......

[Bullfrog]

I haven't worked out the details to run a flow bench test, but I'm pretty sure there are better ways to improve air flow than holes in inner cover.
Ed

[Jack Elliott]

thanks Ed
Have seen posts by people suggesting to drill holes in outer cover (but figure that will also increase the flow of mud and dirt on to aircleaner) and have already cut down rubber funnel as per factory recommendation.I am wanting to work with the original airbox rather than building a new one.
Jack

[DGardner]

I used a K&N filter form a 84 CR500 in my stock 72 wombat filter. I did this so the stock cover had about 1/3 to 1/2 inch gap around the inner filter base for more air flow and still had a stock look to it.

[hodakamax]

Hey Doug, does that filter have a number on it? It's not showing on the K&N site.

Thanks,

Max

[DGardner]

I think 84 85 86 are the same filter and no I don't have a number for it.

[bobwhitman]

I use an 03 foam (Uni/Paul) which has a foam cap, combined with generous drilling of the metal inner cover and doubling or enlarging the hole in the metal outer cover. You then need to construct an enlarged rubber "neck to match & draw air from under the seat.
Bob

[Jack Elliott]

Thanks All
that sounds like the idea!
My apologies for taking this post in a different direction.

[Jack Elliott]

Bob do you still utilize the original wombat wire screen?

[racerclam]

Be aware that a k&N filter is NOT suitable for dirt , they don't filter well , for street you can get away with it . I would stick with the uni filter you can bear oiled foam.

Rich

[hodakamax]

Not to differ with anyone on the filtration capabilities of the K&N filter but my personal experiences show, at least to me, superior filtration compared to many other filters. Oiled foam is certainly a dirt stopper. K&N filters also must be oiled with the recommended K&N product. I converted my Yanmar tractor expensive air filter to a replacement K&N. The tractor is used in extreme dust conditions and has over 200 hours on the same filter. When servicing regularly at no time could I detect any particles past the air filter. I subsequently converted all my trucks and cars (and motorcycles) to K&N filters with the same results. Just my observation.

Max

[bobwhitman]

Jack-
Yes, std Wombat screen is fine. Filter is #33602 on Paul's schematics, NU 5006 on Uni's site..
bob

[Jack Elliott]

Awesome Bob
many thanks
Jack

[racerclam]

My experience with K&N , While working in Vegaas for 25 years at a performance shop I found that customers wit K&N filters and Holley carbs would end up with plugged air bleeds , also those with fuel injected engines would Mass air flow sensors crudded up messing up their state of tune as well as their idle air control motors in the throttle body getting hung up causing idle issues . Also My friend at Red line oil had told me the EVERY oil analysis he had done that customers had sent in that tested hi in silica content found that they were using a K&N . I personally would not even warranty a carb rebuild if they insisted on running that filter.. Besides every time you clean it the pours in the element get bigger. But to each their own.

Rich

[hodakamax]

All good info Rich. I wonder if the street guys just weren't oiling or maintaining their filters. My wife's Camry is approaching 200,000 with a K&N filter and uses no oil between changes. Dust entry tracks are easy to spot and I've seen none. The tractor is my best arguement with over 200 hours in extreme environments. Same story on the dirt bikes I've owned. All I am saying is that my hands on experience differs from theirs. Too much oil on the filter can contaminate the mass air sensor. These are not "a friend told me" quotes but actual use observations. Lotsa variables here too. Improper cleaning can open the mesh (like compressed air or garden hose cleaning) and not enough oil can let silica through. Maybe I should say (or stress) that a properly maintained K&N filter is one of the best filters in my opinion and testing.

Max

PS--My applications don't include high volume/velocity conditions as in a hi-performance carbed automotive use. I suppose that could be a factor. Another thing that should be mentioned when compared to oiled foam a K&N is pleated and has considerably more air flow with its increased surface area.

[racerclam]

actually les filtration area , and as dirt accumulates mainly on the surface of a K&N flow decreases quickly a foam filter catches dirt through out it depth of cells . However new for new the K&N flows more air but when an equal amout of dirt is collected the foam is flowing more air. Even the K&N rep at the SEMA show admitted its porosity is greater which allows more dirt through . I guess since most of my experience was living in the desert of vegas gave me extreme dust examples also.

Rich

[hodakamax]

All a good discussion Rich and deserts are certainly dusty for sure. Kansas clays are so fine I doubt anything short of an air tight barrier would stop it. Anyway I have to keep adding instructions for the K&N which is to keep it cleaned regularly. Again oiled foam is a good one except in the case of a backfiring carbed engine where they tend to disappear. We are for more air flow which creates more horsepower. They produce more with no air cleaner. All kidding aside, I think we all agree that maintaining a clean air supply is of utmost importance for longevity of our engines. Weighing out air flow vs air cleaning the K&N is a really good filter. What's our alternative? Certainly not a factory paper filter.

Maxie

PS--Isn't this a frame discussion? Sorry Doug, hijacked again.

[taber hodaka]

well done all ! -----Clarence

[MTrat]

I've gone clear submerged in river crossings on long CC races several times and find the foam is easy to wring out as part of the 'get back in the race' procedure. Not sure how the K&N would fare....