The GEODYNA 7100 spins slower than the rest of the family. Its measuring speed is listed at under 100 rpm, roughly half the shaft speed the larger models in the range are specified for, and Hofmann still quotes the same ±0.35° angular resolution for it. That is the interesting fact about this machine: the accuracy comes out of the VPI measuring technique rather than out of shaft speed, so the 7100 does not have to work a wheel hard to know what is wrong with it.
It is the compact, LED-display balancer in the line — a machine for the smaller tire shop, the general repair bay adding wheel service, or the second balancer in a busy shop that needs the floor space back.
A slower spin is not a slower machine
Spin speed is the specification buyers most often read backwards. A wheel turning at high speed carries a lot of energy, makes noise, and puts load through the shaft and bearings every cycle of every day. What actually determines the result is how well the machine resolves where the imbalance sits, and the 7100 resolves it to ±0.35° with a published balancing accuracy of 0.035 (1 g). Add the QuickBal short start-stop cycle and belt-driven one-spin balancing and you get a machine that is measured and calm rather than fast and loud — which, in a small shop where the balancer sits ten feet from where you talk to customers, is worth something on its own.
2D SAPE data entry, in plain terms
The 7100 takes offset and rim diameter semi-automatically through its 2D SAPE gauge arm: pull the arm to the rim, and those two values are captured rather than typed. Rim width is entered manually. That split is a genuine cost/benefit decision rather than a cut corner — the two dimensions that are awkward to measure by hand are the ones the machine takes for you, and width, the one anyone can read, stays a keypad entry.
The display is an LED panel with large digits for the weight amount and clear indicators for weight position, and the machine also runs imbalance minimisation and optimisation programs for wheels that will not come right by weight alone.
Clamping and the wheel guard
The wheel clamps on an integrated flange with a quick nut, and a wheel guard is part of the machine. The guard is not a formality: it is the interlock between the operator and a spinning assembly, and any balancer whose guard has been defeated is a balancer that should be taken out of service until it is fixed.
Capacity, and one figure to confirm before you order
Maximum wheel diameter is given on this page’s specification table as 37.8" (960 mm), with a maximum wheel weight of 154 lbs (70 kg). The manual rim diameter range runs to 32" and the semi-automatic rim diameter range to 25", with rim width and offset ranges of 1-20".
Published figures for the maximum tire diameter differ: the specification table on this page lists 37.8", and a second published figure for the same machine lists 32". The gap is almost certainly the distinction between the largest assembly the machine will physically take and the largest rim diameter you can enter. If your work runs at the top of that range, confirm the figure with us in writing before you order — we will get it straight from Hofmann’s own sheet.
Will it fit your bay?
The 7100 is the small-footprint model, which is one of Hofmann’s own listed features for it. The specification table gives 43" x 39.5" x 67". Our product fields give the depth as 40" rather than 39.5"; half an inch will not decide most installations, but if you are planning to the inch against a wall or a workbench, ask us to confirm rather than trusting either number.
Net weight is 154 lbs, and that is a real advantage: it is light enough that repositioning the machine within the shop is a two-person job rather than a rigging job. Power is 230 VAC, single phase, 50/60 Hz, which is not a standard convenience outlet — confirm what is available in the bay, and budget an electrician if it is not already run. Verifying the supply, the access route and the floor space before ordering is the buyer’s responsibility.
Specifications
| Max. wheel diameter |
37.8" (960 mm) |
| Max. wheel weight |
154 lbs (70 kg) |
| Manual rim diameter range |
8-32" |
| Semi-automatic rim diameter range |
8-25" |
| Rim width range |
1-20" |
| Offset range |
1-20" |
| Measuring speed |
under 100 rpm |
| Angular resolution |
±0.35° |
| Shaft |
40 mm diameter, 225 mm long |
| Wheel clamping |
Integrated flange, quick nut |
| Power |
230 VAC, 1 ph, 50/60 Hz |
| Cabinet |
43" x 39.5" x 67" |
| Net weight |
154 lbs (70 kg) |
You will notice we have not quoted a check-spin time. Our two sources for it disagree — the feature list and the specification table give different figures for the same measurement — so we have left it out rather than print the one that reads better. Ask us if cycle time is the number your purchase turns on.
Perfect For
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Small tire shops where floor area is the binding constraint and a 43" wide cabinet earns its keep.
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General repair garages adding wheel balancing without rebuilding a bay around it.
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Busy shops needing a second balancer to keep a lane moving when the main machine is occupied.
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Mobile and satellite operations, given a 154 lbs machine that two people can reposition.
What comes with it
Hofmann lists the wheel guard and the integrated flange with quick nut as part of the machine. The EZ-Collets mobile app is available alongside it — select a vehicle and it compares collets, flanges and quick plates for that wheel, and returns tire and rim data for the vehicle. It is free to download from the Apple and Google stores and needs an email activation.
Our data does not list the cone set supplied in the crate. If a specific mounting accessory decides this purchase, ask us to confirm it in writing first.
Certification, stated plainly
We hold no record of a third-party safety listing for this balancer in our product data, and we are not going to hint at one. Where an insurer, a fleet policy or a local inspection regime requires shop equipment to be listed by an independent testing laboratory, that is a question to answer before purchase. Ask us and we will put it to the manufacturer and pass on exactly what they send.
Delivery and inspection
The machine travels as freight within the contiguous United States. Hofmann equipment carries its own delivery, set-up and instruction arrangement, which is described in the Pick Up and Delivery section further down this page and is worth reading before installation day is planned.
Inspect the shipment before signing for it. Look for crushed corners, punctures and shifted banding, check the display housing and the guard, and write anything you find on the bill of lading while the driver is still there. That note is what keeps a damage claim open.
Warranty
Warranty is handled through our warranty claims page. Please do not take the machine apart to chase a fault before the claim exists — photograph it, keep the packaging if transit damage is plausible, and call us first. Disassembly before a claim is opened is the most reliable way to lose one.
