Simplicity Broadmoor R/S Project

I think your making the right decision to give the front steering a break and work else ware. Love seeing a oppy go together

Thanks, do any of you guys know a good online spot to get opposed valve springs and various stuff?

Front suspension shock mounts are pretty much completed.


Because I assumed the angle on the shocks to be almost too much anyway, I opted to go with only one position for the upper mounting instead of multiple mounting holes. It also simplified the bracket and saved some time.


I pushed on the front end a bit to get a feel for it and it will hold 150-170 lbs or so with maybe 3/4" of sag. That's just a guess not an exact measurement. But it feels like it won't be ultra soft and not too stiff either. Probably stiffer than the #64 adventure edition though as it's setup now. They are 700-750lb springs.


Time will tell if the shocks themselves have much resistance to them or not. If needed I can add golf cart shocks along side the coil overs.  


I also weighed the front end as seen in the pic with wheels attached. 81 lbs so far. That's not light but also not too far off since it's the whole front suspension and forward half of the frame with wheels. 81 lbs plus 100 lbs for the opposed, plus 75 for the 633a transaxle brings us up to 256 lbs. There's still a lot of things to add but we're still on track for a hopefully max 500 lb machine. I could have skimped on the front end steel, it's pretty beefy as it is. But I think I would rather have the extra weight vs break the front end all the time. Besides that, it's all nice and low with none of it over the top of the tires. Should make for a nice planted feel. I don't think tipping sideways will be much of an issue. Actual measured ground clearance 6-3/4" under the skid plate.

Worked on the engine mounting plate. Here is a stock one and the one I changed for comparison.
I cut the ends down a bit and added gussets along the length of both sides. They do not interfere with the engine.


Better view of the gusset seen from the bottom of the mounting plate.


Minor changes were made to the original plan. I intended on having 9" of ground clearance in the middle of the frame
but this was reduced to about 7" same as the front. Also, instead of having the engine completely centered, I decided to move it slightly to the left (only about 3/4") for better belt clearance.


Seen from the bottom, more gussets will be added later on.


Mock up engine in place.


Left front tire to engine clearance. A bit hard to see from this angle but it should be good to go.


Top


Left side


I also did some better measurements on the front suspension to see if I would need extra bump stops or not. It seems the shocks will bottom out before the suspension arms bind up, so that should be good. Also I'll have much more travel than I originally thought. I was hoping for at least 3-4" of travel but it seems I'll end up with about 5" at the wheel. So not too bad. It should be good for high speeds over rough stuff.

This is shaping up very cool. How are you going to run steering over the engine?

Thank you. I'm thinking with two universal joints. The steering shaft will be held somewhere above the engine. There's going to be a sort of upper cage over everything.

Looking really good! After looking at your tire to engine clearance, it looks like it will hit when the suspension allows the tire to move upward. It could be the camera angle though.

Thanks a lot!
The tire should move away slightly as the suspension comes up, it is somewhat close but I think it'll be ok. I figured in a worst case scenario, I could mod the shroud to clear the tire.

mr.modified wrote:

Thanks a lot!
The tire should move away slightly as the suspension comes up, it is somewhat close but I think it'll be ok. I figured in a worst case scenario, I could mod the shroud to clear the tire.

Ah yes, the ol sledgehammer mod

mr.modified wrote:

Thanks, do any of you guys know a good online spot to get opposed valve springs and various stuff?

I have a ratty vertical one you can have, missing carb and tins, had a bunch of mice, but internally complete....

looking pretty custom so far man, gonna be like a buggy...

Thanks for the offer mrshaft but I was gonna try to find some new stuff somewhere. For some reason I had some trouble locating the parts online. I have a surplus of used engines here now so I can piece it together no prob if need be. Haven't got much progress lately, just been busy.

And yeah craftsmanquad, the old sledge hammer trick will fix anything that doesn't turn out quite right.

Update for this month to stay within build off rules. I hate to post without a pic, but I've been kinda busy. I did receive the rear axle, bearings, brake rotor, and all that stuff in the mail. Have not done any math yet on the gearing. At this point I'm going to focus on the #64 Simplicity the next couple weekends to get ready for Haspin 2020, but the next thing I want to do with the RS project is do some mild port work on the engine block so I can start putting it together.

June's super update... Uh... Well I haven't made any more progress with Haspin going on. Since this won't be ready for the TTC in August this year, I'll be focusing on temporary mods to the Adventure Edition to make it a bit more competitive.

Any updates?  No updates?

Unfortunately, no updates. I borrowed the RS shocks to swap onto the adventure edition for the TTC because they lower the front end about 2". I think i'm gonna switch back though because they're a bit too stiff.

Tested out the broadmoor rs shocks on the #64 during the 2020 Top Tractor Challenge. They we're a little stiff for this machine with around 60lbs of weight removed from the front end. But they did give a bit and held up to some pounding. This year's TTC proved to have a few more rough spots with the rock crawl and a big concrete slab pile. I'm not so sure that the RS design would have been up to it with it's 5 or 6" of ground clearance. In all the open sections, steep ramps, dirt piles, tire obstacle, I think it would do well. It would certainly suffer in the mud run with it's small tires and low clearance. The hill climb would have been no problem at all as it was mostly a smooth run. I think at haspin it would definately be decent for hills and higher speed. I'm starting to think that as a TTC competitor though, I probably went a bit too far with the design. Something in between the RS design and the conventional setup would probably be better....

Topic merged with b/o topic.

Thanks Mightyraze for switching these threads around for me! So basically, I got a bit frustrated with this build after the rack and pinion steering setup didn't work out too good. Not only that but it's original intended purpose of entering the 2020 TTC didn't pan out too well, since it wasn't ready in time and also since the TTC courses are a tad rougher than they were in 2019 and now I wonder if I went too far to the extreme on the design. 5" of ground clearance might not be enough. So now I'm trying to decide if I should stick to the original plan, or re-design and come up with something closer to a conventional layout. I'm leaning towards doing that... Probably keeping some of the original ideas like wheels and fiberglass parts but doing away with some of the suspension.

As seen in the Simplicity Adventure Edition thread, I recently picked up a free simplicity broadmoor 728 which has a nice hood/grill ect. I had been looking for one to use as a mold to make fiberglass parts.


Here's a shot of the Broadmoor R/S work area, pretty well cluttered up with all kinds of junk. With the 2021 TTC still quite a ways ahead, there's still time to put together a build for that if I don't get too technical. I think the RS design might have been good for haspin or just riding in general, but it's a bit too complex to figure out when I have other things to do and can't dedicate the time needed to do it right and sort out the issues with it.

Anybody wanna buy a front suspension?