My XR75 Mini-Racer Completed

It ended up being a four year project (a few starts and stops...), but I really enjoyed building it. If any one has any questions ask away, I owe some help to others as i'm normally just a vouyer around here.

AS PURCHASED

MOCKING UP THE REAR SUSPENSION

DECIDED ON MONO SHOCK (ALA DG RACER STYLE)

FITTING UP THE CR80 FORKS

SHORTEN UP THE SPRINGS

ADDED A SWINGARM LOOP TO XR100 SWINGARM

AFTER POWDERCOATING, FITTING IT TOGETHER

SWINGARM AND BRAKE ROD

MOTORS IN

FINISHED1

FINISHED2

Holy crap! Very sweet. ? I'm redoing mine. My frame looks like a chopper, so I'm going to redo the rake and weld in a cradle. But now after seeing yours, I want to also do the rear so I can have a decent re-buildable shock that doesn't cost a house payment.

thats just cool! i remember this thread from awhile back, what kind of t-clamps did you use? and powder coating?

Absolutely SICK!

That was my first bike. A 1978 model in 1983 when I was 12.... ?

Bad A$$!

Awesome Job!

PROPS! ?

Holy crap! Very sweet. ? I'm redoing mine. My frame looks like a chopper, so I'm going to redo the rake and weld in a cradle. But now after seeing yours, I want to also do the rear so I can have a decent re-buildable shock that doesn't cost a house payment.

thats just cool! i remember this thread from awhile back, what kind of t-clamps did you use? and powder coating?

I made the frame brace using the old front motor mounts (new alum. ones are from xr mini racer). I bent a single tube that mated up with welded on brackets at rear of frame. I thought about a more traditional skid plate, but I don't see this seeing heavy abuse, so I opted for the single tube brace. I know what you mean about shocks and $$. Man they can get expensive. This one is a pro-wheel (i - believe), my local shop ordered it out of the pit bike section of parts unlimited catalog. Seems nice, but I haven't tested it hard yet.

Triple's are off a 1990 RM80, which are the same dia. (tubes) as the 1995 CR80 forks. The stem is custom machined and pressed in, as the stock RM was too long and large (dia) for the xr neck. PowderCoating is the easy part, as I do that myself as a secondary income business. Upper is PC'ed in Gloss Black. The lower was sprayed with PPG auto paint, as I couldn't powder (due to heat) as the bearing & dust seal were already on. Could have done it in advance, but I didn't time it right the guy who made the stem..

One of the most difficult aspects of the build was all lthe small things. Cables don't fit, kickstand had to be extended, etc. I didn't take any short cuts, but it was livable because I didn't race the clock, at all.

Thank you for your compliments!

I made the frame brace using the old front motor mounts (new alum. ones are from xr mini racer). I bent a single tube that mated up with welded on brackets at rear of frame. I thought about a more traditional skid plate, but I don't see this seeing heavy abuse, so I opted for the single tube brace. I know what you mean about shocks and $$. Man they can get expensive. This one is a pro-wheel (i - believe), my local shop ordered it out of the pit bike section of parts unlimited catalog. Seems nice, but I haven't tested it hard yet.

Triple's are off a 1990 RM80, which are the same dia. (tubes) as the 1995 CR80 forks. The stem is custom machined and pressed in, as the stock RM was too long and large (dia) for the xr neck. PowderCoating is the easy part, as I do that myself as a secondary income business. Upper is PC'ed in Gloss Black. The lower was sprayed with PPG auto paint, as I couldn't powder (due to heat) as the bearing & dust seal were already on. Could have done it in advance, but I didn't time it right the guy who made the stem..

One of the most difficult aspects of the build was all lthe small things. Cables don't fit, kickstand had to be extended, etc. I didn't take any short cuts, but it was livable because I didn't race the clock, at all.

Thank you for your compliments!

Nice. I am in the process of restoring a 76. The monoshock looks great. On your forks you said you used 1995 CR 80's. Would a 1995 CR triple clamp bolt up to the XR or did you have another reason for going with the RM's. I am trying to decided what forks to go with and your imput would be greatly appreciated. Also do you happen to know what swingarms will bolt up to them also. I am looking at a 81 CR 80 swimarm and not sure if it will work or not. I am going to lay the rear shocks down so I need a longer swingarm.

Excellent Job!!!!!!!!!!!!!!!!!!!!!!!!!

Yes... GREAT job!!

Very sweet. It was pretty cool to begin with but you gotta love the awesome new suspension. Are you worried about frame stretch or anything? I am just wondering because you didn't put a cradle around the motor which would stop the stretch. This bike is sick!

vetrider16 - Wicked Job!! Now i want learn to weld too!! Can you post some dead on side photos of your whole bike? It's just that beautiful! I think all would like to see more of that candy.

POWDER COATING Question's:

1) The color you did the frame etc. in? Is it a good match to Honda's Tahitian Red (like on the Tank) ?? What brand and color code(?) is the Powder?

2) Can the whole engine be powder coated at 400 degrees for a 1/2 hour (eprox.) and Can the head with Valves intact or the cylinder's be done separate as well? Or will it warp?

Thanks for your answers!

-Damon

Nice. I am in the process of restoring a 76. The monoshock looks great. On your forks you said you used 1995 CR 80's. Would a 1995 CR triple clamp bolt up to the XR or did you have another reason for going with the RM's. I am trying to decided what forks to go with and your imput would be greatly appreciated. Also do you happen to know what swingarms will bolt up to them also. I am looking at a 81 CR 80 swimarm and not sure if it will work or not. I am going to lay the rear shocks down so I need a longer swingarm.

Very sweet. It was pretty cool to begin with but you gotta love the awesome new suspension. Are you worried about frame stretch or anything? I am just wondering because you didn't put a cradle around the motor which would stop the stretch. This bike is sick!

POWDER COATING Question's:

1) The color you did the frame etc. in? Is it a good match to Honda's Tahitian Red (like on the Tank) ?? What brand and color code(?) is the Powder?

2) Can the whole engine be powder coated at 400 degrees for a 1/2 hour (eprox.) and Can the head with Valves intact or the cylinder's be done separate as well? Or will it warp?

Thanks for your answers!

-Damon

Q1- I only used a RM upper clamp because I got for .99 cents on flebay. The Honda parts seem to sell for more. I think Honda parts are used more often is conversions / frankenbikes. Modded Xr100's and such... I just studied up the Indside Diameter of what fork seals match, hence the triples would be the same size. I belive you will need to mod / remake almost any modern 80 stem, as the neck on a XR frame is not nearly as long, and the bearing have a smaller inside diameter than many modern(ish) 80's. Unfortunetly, not much of this is plug and play, but I find enjoyment in the modification part.

Swingarms, I'm not 100% sure what will work. Mine is a 79 (i think) XR100 w/ the loop added. Is the 81 CR80 a twin shocker? That will look sweet, I fought long and hard on the decision to go mono or twin shocker. I like both styles. I would guess it will work, as I doubt the distance between mounting points would be less than the old XR frame. You may need to cut spacers / bushings to get it to fit. I bought a metal lathe during this project. In the end, I don't see that I ever would have been able to finish it without the lathe (or pay a machine shop $$). Plus they are super relaxing to play / make parts on.

Q2- I did put a frame cradle under it. You can see it under the first finished pic. But, the jury is still out on its durability, as I haven't ridden the bike hard yet. I'll post a close up pic when I get a chance.

Q3- My color is not the Kick Butt Honda Tatian Red. I would have like to go with that, but the plastic (in that color) are no longer aval. And man do they fetch a pretty penny on flebay when they come up. Therefore I had to settle with the Maier stuff. Its quality is not bad, but the only color its aval. in is the latter Honda (more red) Red. I took one of the plastic pieces to the paint shop and had it matched, thats what I painted the tank with. The powder, used on the frame, swinger, etc., is Eastwood (the hot rod guys). The color is called Bright Red. Its not an exact match, but pretty good. You can get powder match to the exact color, but i'm a small time guy and don't need the minimum quanities required.

While all metal parts on your motor (internal & external) will hold up the 400f, I would worry about the seals. Even if the seals would hold up to the heat, I would tear in apart and do it piece by piece. Its alot of work, but you'll get a far better quality job. Plus if you did it one piece it would be almost impossible to disassemble for future work (the powder would seal it across seams), as the powder would crack. Funny you mention this, as I have a 98 XR80, with the Elec. Ignition, that I want to send to Powroll and have it built to the moon. This motor I will powder with the Black Wrinkle finish. Unfortunetly, I can't justify the funds for that now, but someday...

Cheers:thumbsup:

That is Very cool!!!!!!!!

hey man nice bike, would you be able to tell me just exactly what air filter that is hangin off the carby so i can order one for my little XR80 project bike. thanks

Ah, awesome. I didn't see it until it was pointed out, very cool. In my opinion the single tube will be just fine, it just doesn't protect the side of the motor as much, big deal. I love this bike.

hey man nice bike, would you be able to tell me just exactly what air filter that is hangin off the carby so i can order one for my little XR80 project bike. thanks

It is a K&N. Model # on filter is F019E4. I do have a XR100 carb (Keihen PK series) on mine, not sure if the neck's are the same size? It does fit behind the Maier # plate real nice, but I welded on new tabs for the body work, as the original XR75 has plug in bullet- style (into rubber grommets) mounts. Hope this helps.

Thats one of the coolest builds ive ever seen!!!! i like seeing custom parts:thumbsup:

It is a K&N. Model # on filter is F019E4. I do have a XR100 carb (Keihen PK series) on mine, not sure if the neck's are the same size? It does fit behind the Maier # plate real nice, but I welded on new tabs for the body work, as the original XR75 has plug in bullet- style (into rubber grommets) mounts. Hope this helps.

ok so did the carb bolt right up or did you have to do some modifying to it, im not runnig side plates so there is no concern on spacial issues. did you have to jet it down at all or did it runn good with the stock 100 jets? sorry for all the questions im havin problems with my bike runnin right at this point.

Vet,

What brand and size rims and spokes did you use

ok so did the carb bolt right up or did you have to do some modifying to it, im not runnig side plates so there is no concern on spacial issues. did you have to jet it down at all or did it runn good with the stock 100 jets? sorry for all the questions im havin problems with my bike runnin right at this point.

Vet,

What brand and size rims and spokes did you use

Q1- 95 M.J. / 45 S.J., need to get a different needle right now, as it is in top position, and still runs on after thrtle. is closed. Other than that it runs good. I'm not sure of the specific year of my intake, but yes, it did bolt up. Keep in mind i'm near milwaukee, wi, where we are about 6" above sea level (compared to you) and the elevation change is about the same as kate moss's upper torso:lol: , so my jetting may not apply to you.

Q2- Rims are stock 75. I debated about changing size, for greater tire availibility. Many go with a larger dia front (of a CR80) but I didn't like the look. Same go for smaller, say off of KLX110, i thought that would be kinda cool. There again I was concerned of tampering with the original look too much. I did have to drill out my rims for the heavy duty nips, but thats no big deal. The hub was ok, a tight fit turning the corner when lacing. But the wheels feel real stought. The XR rim seems like a good part, of course heavier than modern aluminum.

The spokes are heavy duty stainless (buchanan) I believe. I got them from east coast wheel, though I read somewhere he's out of business now? I would check with Buchanan though, they do all kinds of custom stuff. I did have to drill out my rims for the heavy duty nips, but thats no big deal. The hub was ok, a tight fit turning the corner when lacing. But the wheels feel real stought. The XR rim seems like a good part, of course heavier than modern aluminum.